21723887619 has 24 divisors (see below), whose sum is σ = 37420860672. Its totient is φ = 11873925360.

The previous prime is 21723887611. The next prime is 21723887629. The reversal of 21723887619 is 91678832712.

It is a happy number.

21723887619 is a `hidden beast` number, since 2 + 17 + 2 + 3 + 8 + 8 + 7 + 619 = 666.

It is not a de Polignac number, because 21723887619 - 2³ = 21723887611 is a prime.

It is a super-2 number, since 2×21723887619² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21723887611) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7494717 + ... + 7497614.

It is an arithmetic number, because the mean of its divisors is an integer number (1559202528).

Almost surely, 2^21723887619 is an apocalyptic number.

21723887619 is a deficient number, since it is larger than the sum of its proper divisors (15696973053).

21723887619 is a wasteful number, since it uses less digits than its factorization.

21723887619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14992367 (or 14992364 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 54.

The spelling of 21723887619 in words is "twenty-one billion, seven hundred twenty-three million, eight hundred eighty-seven thousand, six hundred nineteen".