900638729 has 4 divisors (see below), whose sum is σ = 901345284. Its totient is φ = 899932176.

The previous prime is 900638681. The next prime is 900638743. The reversal of 900638729 is 927836009.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 302934025 + 597704704 = 17405^2 + 24448^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-900638729 is a prime.

It is a super-2 number, since 2×900638729² = 1622300240349470882, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 900638729.

It is not an unprimeable number, because it can be changed into a prime (900638429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 351362 + ... + 353915.

It is an arithmetic number, because the mean of its divisors is an integer number (225336321).

Almost surely, 2^900638729 is an apocalyptic number.

It is an amenable number.

900638729 is a deficient number, since it is larger than the sum of its proper divisors (706555).

900638729 is a wasteful number, since it uses less digits than its factorization.

900638729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 706554.

The product of its (nonzero) digits is 163296, while the sum is 44.

The square root of 900638729 is about 30010.6435952313. The cubic root of 900638729 is about 965.7177328425.

The spelling of 900638729 in words is "nine hundred million, six hundred thirty-eight thousand, seven hundred twenty-nine".