21511555132 has 48 divisors (see below), whose sum is σ = 40820848992. Its totient is φ = 9879367680.

The previous prime is 21511555103. The next prime is 21511555139. The reversal of 21511555132 is 23155511512.

It is a junction number, because it is equal to n+sod(n) for n = 21511555094 and 21511555103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21511555139) 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 in 15 ways as a sum of consecutive naturals, for example, 4714132 + ... + 4718692.

It is an arithmetic number, because the mean of its divisors is an integer number (850434354).

Almost surely, 2^21511555132 is an apocalyptic number.

It is an amenable number.

21511555132 is a deficient number, since it is larger than the sum of its proper divisors (19309293860).

21511555132 is a wasteful number, since it uses less digits than its factorization.

21511555132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6238 (or 6236 counting only the distinct ones).

The product of its digits is 7500, while the sum is 31.

The spelling of 21511555132 in words is "twenty-one billion, five hundred eleven million, five hundred fifty-five thousand, one hundred thirty-two".