634923390 has 64 divisors (see below), whose sum is σ = 1582804800. Its totient is φ = 162806784.

The previous prime is 634923389. The next prime is 634923391. The reversal of 634923390 is 93329436.

It is an interprime number because it is at equal distance from previous prime (634923389) and next prime (634923391).

It is a super-2 number, since 2×634923390² = 806255422338184200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (634923391) 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, 232674 + ... + 235386.

It is an arithmetic number, because the mean of its divisors is an integer number (24731325).

Almost surely, 2^634923390 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 634923390, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (791402400).

634923390 is an abundant number, since it is smaller than the sum of its proper divisors (947881410).

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

634923390 is a wasteful number, since it uses less digits than its factorization.

634923390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3021.

The product of its (nonzero) digits is 104976, while the sum is 39.

The square root of 634923390 is about 25197.6862033005. The cubic root of 634923390 is about 859.4892361022.

The spelling of 634923390 in words is "six hundred thirty-four million, nine hundred twenty-three thousand, three hundred ninety".