642381975 has 144 divisors (see below), whose sum is σ = 1301925600. Its totient is φ = 310210560.

The previous prime is 642381937. The next prime is 642381991. The reversal of 642381975 is 579183246.

It is not a de Polignac number, because 642381975 - 2¹³ = 642373783 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 642381975.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 7217731 + ... + 7217819.

It is an arithmetic number, because the mean of its divisors is an integer number (9041150).

Almost surely, 2^642381975 is an apocalyptic number.

642381975 is an abundant number, since it is smaller than the sum of its proper divisors (659543625).

642381975 is a wasteful number, since it uses less digits than its factorization.

642381975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 151 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 642381975 is about 25345.2554731650. The cubic root of 642381975 is about 862.8416793706.

The spelling of 642381975 in words is "six hundred forty-two million, three hundred eighty-one thousand, nine hundred seventy-five".