21969990895 has 4 divisors (see below), whose sum is σ = 26363989080. Its totient is φ = 17575992712.

The previous prime is 21969990877. The next prime is 21969990899. The reversal of 21969990895 is 59809996912.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21969990895 - 2⁵ = 21969990863 is a prime.

It is a Smith number, since the sum of its digits (67) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 21969990895.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21969990899) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2196999085 + ... + 2196999094.

It is an arithmetic number, because the mean of its divisors is an integer number (6590997270).

Almost surely, 2^21969990895 is an apocalyptic number.

21969990895 is a deficient number, since it is larger than the sum of its proper divisors (4393998185).

21969990895 is an equidigital number, since it uses as much as digits as its factorization.

21969990895 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4393998184.

The product of its (nonzero) digits is 28343520, while the sum is 67.

The spelling of 21969990895 in words is "twenty-one billion, nine hundred sixty-nine million, nine hundred ninety thousand, eight hundred ninety-five".