1254389640 has 128 divisors (see below), whose sum is σ = 4487823360. Its totient is φ = 274247424.

The previous prime is 1254389639. The next prime is 1254389641. The reversal of 1254389640 is 469834521.

It is an interprime number because it is at equal distance from previous prime (1254389639) and next prime (1254389641).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 1254389592 and 1254389601.

It is not an unprimeable number, because it can be changed into a prime (1254389641) 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, 13144 + ... + 51783.

It is an arithmetic number, because the mean of its divisors is an integer number (35061120).

Almost surely, 2^1254389640 is an apocalyptic number.

1254389640 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 1254389640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2243911680).

1254389640 is an abundant number, since it is smaller than the sum of its proper divisors (3233433720).

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

1254389640 is a wasteful number, since it uses less digits than its factorization.

1254389640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64971 (or 64967 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 42.

The square root of 1254389640 is about 35417.3635382421. The cubic root of 1254389640 is about 1078.4768308730.

The spelling of 1254389640 in words is "one billion, two hundred fifty-four million, three hundred eighty-nine thousand, six hundred forty".