642826031 has 4 divisors (see below), whose sum is σ = 676659000. Its totient is φ = 608993064.

The previous prime is 642826021. The next prime is 642826109. The reversal of 642826031 is 130628246.

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

It is a cyclic number.

It is not a de Polignac number, because 642826031 - 2²² = 638631727 is a prime.

It is a super-2 number, since 2×642826031² = 826450612262425922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642826021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16916456 + ... + 16916493.

It is an arithmetic number, because the mean of its divisors is an integer number (169164750).

Almost surely, 2^642826031 is an apocalyptic number.

642826031 is a deficient number, since it is larger than the sum of its proper divisors (33832969).

642826031 is a wasteful number, since it uses less digits than its factorization.

642826031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33832968.

The product of its (nonzero) digits is 13824, while the sum is 32.

The square root of 642826031 is about 25354.0141003353. The cubic root of 642826031 is about 863.0404509155.

The spelling of 642826031 in words is "six hundred forty-two million, eight hundred twenty-six thousand, thirty-one".