21732123751 has 4 divisors (see below), whose sum is σ = 23403825592. Its totient is φ = 20060421912.

The previous prime is 21732123713. The next prime is 21732123767. The reversal of 21732123751 is 15732123712.

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

It is a cyclic number.

It is not a de Polignac number, because 21732123751 - 2⁹ = 21732123239 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21732123701) 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 3 ways as a sum of consecutive naturals, for example, 835850901 + ... + 835850926.

It is an arithmetic number, because the mean of its divisors is an integer number (5850956398).

Almost surely, 2^21732123751 is an apocalyptic number.

21732123751 is a deficient number, since it is larger than the sum of its proper divisors (1671701841).

21732123751 is a wasteful number, since it uses less digits than its factorization.

21732123751 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1671701840.

The product of its digits is 17640, while the sum is 34.

The spelling of 21732123751 in words is "twenty-one billion, seven hundred thirty-two million, one hundred twenty-three thousand, seven hundred fifty-one".