690042138 has 32 divisors (see below), whose sum is σ = 1464246720. Its totient is φ = 216042240.

The previous prime is 690042137. The next prime is 690042149. The reversal of 690042138 is 831240096.

It is a super-2 number, since 2×690042138² = 952316304431222088, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 690042099 and 690042108.

It is not an unprimeable number, because it can be changed into a prime (690042137) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45273 + ... + 58563.

It is an arithmetic number, because the mean of its divisors is an integer number (45757710).

Almost surely, 2^690042138 is an apocalyptic number.

690042138 is an abundant number, since it is smaller than the sum of its proper divisors (774204582).

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

690042138 is a wasteful number, since it uses less digits than its factorization.

690042138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13822.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 690042138 is about 26268.6531440042. The cubic root of 690042138 is about 883.6735800285.

The spelling of 690042138 in words is "six hundred ninety million, forty-two thousand, one hundred thirty-eight".