21995100645 has 48 divisors (see below), whose sum is σ = 41152416768. Its totient is φ = 10002195840.

The previous prime is 21995100637. The next prime is 21995100661. The reversal of 21995100645 is 54600159912.

It is not a de Polignac number, because 21995100645 - 2³ = 21995100637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21995100597 and 21995100606.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 62047 + ... + 218723.

It is an arithmetic number, because the mean of its divisors is an integer number (857342016).

Almost surely, 2^21995100645 is an apocalyptic number.

It is an amenable number.

21995100645 is a deficient number, since it is larger than the sum of its proper divisors (19157316123).

21995100645 is a wasteful number, since it uses less digits than its factorization.

21995100645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 156890 (or 156883 counting only the distinct ones).

The product of its (nonzero) digits is 97200, while the sum is 42.

The spelling of 21995100645 in words is "twenty-one billion, nine hundred ninety-five million, one hundred thousand, six hundred forty-five".