21755035856 has 20 divisors (see below), whose sum is σ = 42472144704. Its totient is φ = 10794482400.

The previous prime is 21755035807. The next prime is 21755035867. The reversal of 21755035856 is 65853055712.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21755035856.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5187560 + ... + 5191751.

Almost surely, 2^21755035856 is an apocalyptic number.

It is an amenable number.

21755035856 is a deficient number, since it is larger than the sum of its proper divisors (20717108848).

21755035856 is a wasteful number, since it uses less digits than its factorization.

21755035856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10379450 (or 10379444 counting only the distinct ones).

The product of its (nonzero) digits is 1260000, while the sum is 47.

The spelling of 21755035856 in words is "twenty-one billion, seven hundred fifty-five million, thirty-five thousand, eight hundred fifty-six".