21771415725 has 48 divisors (see below), whose sum is σ = 36398973888. Its totient is φ = 11481648640.

The previous prime is 21771415697. The next prime is 21771415733. The reversal of 21771415725 is 52751417712.

It is not a de Polignac number, because 21771415725 - 2⁷ = 21771415597 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4949227 + ... + 4953623.

It is an arithmetic number, because the mean of its divisors is an integer number (758311956).

Almost surely, 2^21771415725 is an apocalyptic number.

21771415725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21771415725 is a deficient number, since it is larger than the sum of its proper divisors (14627558163).

21771415725 is a wasteful number, since it uses less digits than its factorization.

21771415725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5134 (or 5129 counting only the distinct ones).

The product of its digits is 137200, while the sum is 42.

The spelling of 21771415725 in words is "twenty-one billion, seven hundred seventy-one million, four hundred fifteen thousand, seven hundred twenty-five".