1234839640 has 128 divisors (see below), whose sum is σ = 3128025600. Its totient is φ = 436423680.

The previous prime is 1234839637. The next prime is 1234839649. The reversal of 1234839640 is 469384321.

It is a happy number.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1234839593 and 1234839602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1234839649) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 715819 + ... + 717541.

It is an arithmetic number, because the mean of its divisors is an integer number (24437700).

Almost surely, 2^1234839640 is an apocalyptic number.

1234839640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1234839640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1564012800).

1234839640 is an abundant number, since it is smaller than the sum of its proper divisors (1893185960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1234839640 is a wasteful number, since it uses less digits than its factorization.

1234839640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1817 (or 1813 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The square root of 1234839640 is about 35140.2851439768. The cubic root of 1234839640 is about 1072.8446853891.

The spelling of 1234839640 in words is "one billion, two hundred thirty-four million, eight hundred thirty-nine thousand, six hundred forty".