21623542445 has 16 divisors (see below), whose sum is σ = 27478683648. Its totient is φ = 16278846720.

The previous prime is 21623542441. The next prime is 21623542453. The reversal of 21623542445 is 54424532612.

It is not a de Polignac number, because 21623542445 - 2² = 21623542441 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21623542399 and 21623542408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21623542441) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 736232 + ... + 765038.

It is an arithmetic number, because the mean of its divisors is an integer number (1717417728).

Almost surely, 2^21623542445 is an apocalyptic number.

It is an amenable number.

21623542445 is a deficient number, since it is larger than the sum of its proper divisors (5855141203).

21623542445 is a wasteful number, since it uses less digits than its factorization.

21623542445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37660.

The product of its digits is 230400, while the sum is 38.

The spelling of 21623542445 in words is "twenty-one billion, six hundred twenty-three million, five hundred forty-two thousand, four hundred forty-five".