634579920 has 400 divisors, whose sum is σ = 2460175872. Its totient is φ = 151165440.

The previous prime is 634579909. The next prime is 634579921. The reversal of 634579920 is 29975436.

It is a happy number.

634579920 is a `hidden beast` number, since 634 + 5 + 7 + 9 + 9 + 2 + 0 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634579921) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 20470305 + ... + 20470335.

Almost surely, 2^634579920 is an apocalyptic number.

634579920 is a gapful number since it is divisible by the number (60) 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 634579920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1230087936).

634579920 is an abundant number, since it is smaller than the sum of its proper divisors (1825595952).

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

634579920 is an equidigital number, since it uses as much as digits as its factorization.

634579920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84 (or 54 counting only the distinct ones).

The product of its (nonzero) digits is 408240, while the sum is 45.

The square root of 634579920 is about 25190.8697745830. The cubic root of 634579920 is about 859.3342242163.

The spelling of 634579920 in words is "six hundred thirty-four million, five hundred seventy-nine thousand, nine hundred twenty".