21925709127 has 20 divisors (see below), whose sum is σ = 37432252176. Its totient is φ = 12528976320.

The previous prime is 21925709107. The next prime is 21925709131. The reversal of 21925709127 is 72190752912.

It is not a de Polignac number, because 21925709127 - 2¹⁴ = 21925692743 is a prime.

It is a super-2 number, since 2×21925709127² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21925709107) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 19334274 + ... + 19335407.

Almost surely, 2^21925709127 is an apocalyptic number.

21925709127 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

21925709127 is a deficient number, since it is larger than the sum of its proper divisors (15506543049).

21925709127 is an equidigital number, since it uses as much as digits as its factorization.

21925709127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38669700 (or 38669691 counting only the distinct ones).

The product of its (nonzero) digits is 158760, while the sum is 45.

The spelling of 21925709127 in words is "twenty-one billion, nine hundred twenty-five million, seven hundred nine thousand, one hundred twenty-seven".