642181285 has 16 divisors (see below), whose sum is σ = 813980160. Its totient is φ = 485023680.

The previous prime is 642181277. The next prime is 642181301. The reversal of 642181285 is 582181246.

It is not a de Polignac number, because 642181285 - 2³ = 642181277 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16300 + ... + 39370.

It is an arithmetic number, because the mean of its divisors is an integer number (50873760).

Almost surely, 2^642181285 is an apocalyptic number.

It is an amenable number.

642181285 is a deficient number, since it is larger than the sum of its proper divisors (171798875).

642181285 is a wasteful number, since it uses less digits than its factorization.

642181285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23388.

The product of its digits is 30720, while the sum is 37.

The square root of 642181285 is about 25341.2960402581. The cubic root of 642181285 is about 862.7518150119.

The spelling of 642181285 in words is "six hundred forty-two million, one hundred eighty-one thousand, two hundred eighty-five".