642221125 has 96 divisors (see below), whose sum is σ = 1024987392. Its totient is φ = 393120000.

The previous prime is 642221117. The next prime is 642221137. The reversal of 642221125 is 521122246.

It is not a de Polignac number, because 642221125 - 2³ = 642221117 is a prime.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (25).

642221125 is a Rhonda number in base 10.

Its product of digits (1920) is a multiple of the sum of its prime factors (192).

It is a self number, because there is not a number n which added to its sum of digits gives 642221125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6358575 + ... + 6358675.

It is an arithmetic number, because the mean of its divisors is an integer number (10676952).

Almost surely, 2^642221125 is an apocalyptic number.

642221125 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

642221125 is a deficient number, since it is larger than the sum of its proper divisors (382766267).

642221125 is a wasteful number, since it uses less digits than its factorization.

642221125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 169 counting only the distinct ones).

The product of its digits is 1920, while the sum is 25.

The square root of 642221125 is about 25342.0820967812. The cubic root of 642221125 is about 862.7696559354.

The spelling of 642221125 in words is "six hundred forty-two million, two hundred twenty-one thousand, one hundred twenty-five".