21052702649 has 16 divisors (see below), whose sum is σ = 23195177280. Its totient is φ = 18948600000.

The previous prime is 21052702633. The next prime is 21052702661. The reversal of 21052702649 is 94620725012.

It is not a de Polignac number, because 21052702649 - 2⁴ = 21052702633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21052702049) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1733699 + ... + 1745799.

It is an arithmetic number, because the mean of its divisors is an integer number (1449698580).

Almost surely, 2^21052702649 is an apocalyptic number.

It is an amenable number.

21052702649 is a deficient number, since it is larger than the sum of its proper divisors (2142474631).

21052702649 is a wasteful number, since it uses less digits than its factorization.

21052702649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13672.

The product of its (nonzero) digits is 60480, while the sum is 38.

The spelling of 21052702649 in words is "twenty-one billion, fifty-two million, seven hundred two thousand, six hundred forty-nine".