21722209725 has 24 divisors (see below), whose sum is σ = 36678188160. Its totient is φ = 11338683520.

The previous prime is 21722209711. The next prime is 21722209727. The reversal of 21722209725 is 52790222712.

It is not a de Polignac number, because 21722209725 - 2⁴ = 21722209709 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21722209727) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3077640 + ... + 3084689.

It is an arithmetic number, because the mean of its divisors is an integer number (1528257840).

Almost surely, 2^21722209725 is an apocalyptic number.

21722209725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21722209725 is a deficient number, since it is larger than the sum of its proper divisors (14955978435).

21722209725 is a wasteful number, since it uses less digits than its factorization.

21722209725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6162389 (or 6162384 counting only the distinct ones).

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

The spelling of 21722209725 in words is "twenty-one billion, seven hundred twenty-two million, two hundred nine thousand, seven hundred twenty-five".