642331287 has 12 divisors (see below), whose sum is σ = 999182184. Its totient is φ = 395280720.

The previous prime is 642331267. The next prime is 642331321. The reversal of 642331287 is 782133246.

It is a happy number.

642331287 is a `hidden beast` number, since 6 + 42 + 331 + 287 = 666.

It is not a de Polignac number, because 642331287 - 2¹⁶ = 642265751 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642331267) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2744889 + ... + 2745122.

It is an arithmetic number, because the mean of its divisors is an integer number (83265182).

Almost surely, 2^642331287 is an apocalyptic number.

642331287 is a deficient number, since it is larger than the sum of its proper divisors (356850897).

642331287 is a wasteful number, since it uses less digits than its factorization.

642331287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5490030 (or 5490027 counting only the distinct ones).

The product of its digits is 48384, while the sum is 36.

The square root of 642331287 is about 25344.2555029734. The cubic root of 642331287 is about 862.8189842188.

The spelling of 642331287 in words is "six hundred forty-two million, three hundred thirty-one thousand, two hundred eighty-seven".