42631209 has 24 divisors (see below), whose sum is σ = 63598080. Its totient is φ = 27502848.

The previous prime is 42631181. The next prime is 42631243. The reversal of 42631209 is 90213624.

42631209 is a `hidden beast` number, since 4 + 2 + 631 + 20 + 9 = 666.

It is not a de Polignac number, because 42631209 - 2⁷ = 42631081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (42631409) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40512 + ... + 41550.

It is an arithmetic number, because the mean of its divisors is an integer number (2649920).

Almost surely, 2^42631209 is an apocalyptic number.

It is an amenable number.

42631209 is a deficient number, since it is larger than the sum of its proper divisors (20966871).

42631209 is a wasteful number, since it uses less digits than its factorization.

42631209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1189 (or 1186 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The square root of 42631209 is about 6529.2579210811. The cubic root of 42631209 is about 349.3353618026.

The spelling of 42631209 in words is "forty-two million, six hundred thirty-one thousand, two hundred nine".