21297895766 has 24 divisors (see below), whose sum is σ = 39348696456. Its totient is φ = 8590747200.

The previous prime is 21297895733. The next prime is 21297895799. The reversal of 21297895766 is 66759879212.

It is an interprime number because it is at equal distance from previous prime (21297895733) and next prime (21297895799).

It is a junction number, because it is equal to n+sod(n) for n = 21297895699 and 21297895708.

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, 6390260 + ... + 6393591.

It is an arithmetic number, because the mean of its divisors is an integer number (1639529019).

Almost surely, 2^21297895766 is an apocalyptic number.

21297895766 is a deficient number, since it is larger than the sum of its proper divisors (18050800690).

21297895766 is a wasteful number, since it uses less digits than its factorization.

21297895766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12783884 (or 12783877 counting only the distinct ones).

The product of its digits is 22861440, while the sum is 62.

The spelling of 21297895766 in words is "twenty-one billion, two hundred ninety-seven million, eight hundred ninety-five thousand, seven hundred sixty-six".