21580611628 has 6 divisors (see below), whose sum is σ = 37766070356. Its totient is φ = 10790305812.

The previous prime is 21580611623. The next prime is 21580611629. The reversal of 21580611628 is 82611608512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21580611623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2697576450 + ... + 2697576457.

Almost surely, 2^21580611628 is an apocalyptic number.

It is an amenable number.

21580611628 is a deficient number, since it is larger than the sum of its proper divisors (16185458728).

21580611628 is a wasteful number, since it uses less digits than its factorization.

21580611628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5395152911 (or 5395152909 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 40.

The spelling of 21580611628 in words is "twenty-one billion, five hundred eighty million, six hundred eleven thousand, six hundred twenty-eight".