634890840 has 128 divisors (see below), whose sum is σ = 2032128000. Its totient is φ = 158128128.

The previous prime is 634890811. The next prime is 634890853. The reversal of 634890840 is 48098436.

It is a junction number, because it is equal to n+sod(n) for n = 634890792 and 634890801.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 282441 + ... + 284679.

It is an arithmetic number, because the mean of its divisors is an integer number (15876000).

Almost surely, 2^634890840 is an apocalyptic number.

634890840 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 634890840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1016064000).

634890840 is an abundant number, since it is smaller than the sum of its proper divisors (1397237160).

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

634890840 is a wasteful number, since it uses less digits than its factorization.

634890840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2409 (or 2405 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 42.

The square root of 634890840 is about 25197.0403023847. The cubic root of 634890840 is about 859.4745483182.

The spelling of 634890840 in words is "six hundred thirty-four million, eight hundred ninety thousand, eight hundred forty".