21432632456 has 8 divisors (see below), whose sum is σ = 40186185870. Its totient is φ = 10716316224.

The previous prime is 21432632399. The next prime is 21432632467. The reversal of 21432632456 is 65423623412.

It can be written as a sum of positive squares in only one way, i.e., 21313080100 + 119552356 = 145990^2 + 10934^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1339539521 + ... + 1339539536.

Almost surely, 2^21432632456 is an apocalyptic number.

It is an amenable number.

21432632456 is a deficient number, since it is larger than the sum of its proper divisors (18753553414).

21432632456 is a wasteful number, since it uses less digits than its factorization.

21432632456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2679079063 (or 2679079059 counting only the distinct ones).

The product of its digits is 207360, while the sum is 38.

The spelling of 21432632456 in words is "twenty-one billion, four hundred thirty-two million, six hundred thirty-two thousand, four hundred fifty-six".