21722723725 has 12 divisors (see below), whose sum is σ = 27377756020. Its totient is φ = 17093289600.

The previous prime is 21722723723. The next prime is 21722723749. The reversal of 21722723725 is 52732722712.

It can be written as a sum of positive squares in 6 ways, for example, as 4942371204 + 16780352521 = 70302^2 + 129539^2 .

It is not a de Polignac number, because 21722723725 - 2¹ = 21722723723 is a prime.

It is a hoax number, since the sum of its digits (40) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21722723723) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7120680 + ... + 7123729.

Almost surely, 2^21722723725 is an apocalyptic number.

21722723725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21722723725 is a deficient number, since it is larger than the sum of its proper divisors (5655032295).

21722723725 is a wasteful number, since it uses less digits than its factorization.

21722723725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14244480 (or 14244475 counting only the distinct ones).

The product of its digits is 164640, while the sum is 40.

The spelling of 21722723725 in words is "twenty-one billion, seven hundred twenty-two million, seven hundred twenty-three thousand, seven hundred twenty-five".