642253126 has 4 divisors (see below), whose sum is σ = 963379692. Its totient is φ = 321126562.

The previous prime is 642253093. The next prime is 642253147. The reversal of 642253126 is 621352246.

It is a semiprime because it is the product of two primes.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160563280 + ... + 160563283.

It is an arithmetic number, because the mean of its divisors is an integer number (240844923).

Almost surely, 2^642253126 is an apocalyptic number.

642253126 is a deficient number, since it is larger than the sum of its proper divisors (321126566).

642253126 is a wasteful number, since it uses less digits than its factorization.

642253126 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 321126565.

The product of its digits is 17280, while the sum is 31.

The square root of 642253126 is about 25342.7134695557. The cubic root of 642253126 is about 862.7839859079.

The spelling of 642253126 in words is "six hundred forty-two million, two hundred fifty-three thousand, one hundred twenty-six".