21642137175 has 12 divisors (see below), whose sum is σ = 35781666920. Its totient is φ = 11542473120.

The previous prime is 21642137171. The next prime is 21642137177. The reversal of 21642137175 is 57173124612.

It is not a de Polignac number, because 21642137175 - 2² = 21642137171 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21642137171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 144280840 + ... + 144280989.

Almost surely, 2^21642137175 is an apocalyptic number.

21642137175 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21642137175 is a deficient number, since it is larger than the sum of its proper divisors (14139529745).

21642137175 is a wasteful number, since it uses less digits than its factorization.

21642137175 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288561842 (or 288561837 counting only the distinct ones).

The product of its digits is 70560, while the sum is 39.

The spelling of 21642137175 in words is "twenty-one billion, six hundred forty-two million, one hundred thirty-seven thousand, one hundred seventy-five".