425978640 has 120 divisors (see below), whose sum is σ = 1463953920. Its totient is φ = 110944512.

The previous prime is 425978627. The next prime is 425978681. The reversal of 425978640 is 46879524.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 24081 + ... + 37839.

It is an arithmetic number, because the mean of its divisors is an integer number (12199616).

Almost surely, 2^425978640 is an apocalyptic number.

425978640 is a gapful number since it is divisible by the number (40) formed by its first and last digit.

425978640 is the 10320-th decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 425978640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (731976960).

425978640 is an abundant number, since it is smaller than the sum of its proper divisors (1037975280).

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

425978640 is a wasteful number, since it uses less digits than its factorization.

425978640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13821 (or 13812 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The square root of 425978640 is about 20639.2499863731. The cubic root of 425978640 is about 752.4239442196.

The spelling of 425978640 in words is "four hundred twenty-five million, nine hundred seventy-eight thousand, six hundred forty".