21235452705 has 24 divisors (see below), whose sum is σ = 36829915200. Its totient is φ = 11318868000.

The previous prime is 21235452677. The next prime is 21235452731. The reversal of 21235452705 is 50725453212.

21235452705 is a `hidden beast` number, since 2 + 123 + 5 + 4 + 527 + 0 + 5 = 666.

It is not a de Polignac number, because 21235452705 - 2⁹ = 21235452193 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21235452705.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 62421 + ... + 215330.

It is an arithmetic number, because the mean of its divisors is an integer number (1534579800).

Almost surely, 2^21235452705 is an apocalyptic number.

It is an amenable number.

21235452705 is a deficient number, since it is larger than the sum of its proper divisors (15594462495).

21235452705 is a wasteful number, since it uses less digits than its factorization.

21235452705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 279461 (or 279458 counting only the distinct ones).

The product of its (nonzero) digits is 84000, while the sum is 36.

The spelling of 21235452705 in words is "twenty-one billion, two hundred thirty-five million, four hundred fifty-two thousand, seven hundred five".