21506740277725 has 12 divisors (see below), whose sum is σ = 27235769817024. Its totient is φ = 16839320046320.

The previous prime is 21506740277683. The next prime is 21506740277779. The reversal of 21506740277725 is 52777204760512.

It is not a de Polignac number, because 21506740277725 - 2²³ = 21506731889117 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9151803199 + ... + 9151805548.

It is an arithmetic number, because the mean of its divisors is an integer number (2269647484752).

Almost surely, 2^{21506740277725} is an apocalyptic number.

21506740277725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21506740277725 is a deficient number, since it is larger than the sum of its proper divisors (5729029539299).

21506740277725 is a wasteful number, since it uses less digits than its factorization.

21506740277725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18303608804 (or 18303608799 counting only the distinct ones).

The product of its (nonzero) digits is 11524800, while the sum is 55.

The spelling of 21506740277725 in words is "twenty-one trillion, five hundred six billion, seven hundred forty million, two hundred seventy-seven thousand, seven hundred twenty-five".