642881231 has 16 divisors (see below), whose sum is σ = 690941664. Its totient is φ = 596004864.

The previous prime is 642881221. The next prime is 642881243. The reversal of 642881231 is 132188246.

It is a cyclic number.

It is not a de Polignac number, because 642881231 - 2¹⁴ = 642864847 is a prime.

It is a super-2 number, since 2×642881231² = 826592554344150722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 642881191 and 642881200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642881201) 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, 949265 + ... + 949941.

It is an arithmetic number, because the mean of its divisors is an integer number (43183854).

Almost surely, 2^642881231 is an apocalyptic number.

642881231 is a deficient number, since it is larger than the sum of its proper divisors (48060433).

642881231 is a wasteful number, since it uses less digits than its factorization.

642881231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1450.

The product of its digits is 18432, while the sum is 35.

The square root of 642881231 is about 25355.1026619890. The cubic root of 642881231 is about 863.0651535395.

The spelling of 642881231 in words is "six hundred forty-two million, eight hundred eighty-one thousand, two hundred thirty-one".