21065495896 has 8 divisors (see below), whose sum is σ = 39497804820. Its totient is φ = 10532747944.

The previous prime is 21065495849. The next prime is 21065495897. The reversal of 21065495896 is 69859456012.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (55) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21065495897) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1316593486 + ... + 1316593501.

Almost surely, 2^21065495896 is an apocalyptic number.

It is an amenable number.

21065495896 is a deficient number, since it is larger than the sum of its proper divisors (18432308924).

21065495896 is a wasteful number, since it uses less digits than its factorization.

21065495896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2633186993 (or 2633186989 counting only the distinct ones).

The product of its (nonzero) digits is 4665600, while the sum is 55.

It can be divided in two parts, 21065 and 495896, that added together give a square (516961 = 719²).

The spelling of 21065495896 in words is "twenty-one billion, sixty-five million, four hundred ninety-five thousand, eight hundred ninety-six".