21554331432 has 32 divisors (see below), whose sum is σ = 55743962400. Its totient is φ = 6937025984.

The previous prime is 21554331397. The next prime is 21554331439. The reversal of 21554331432 is 23413345512.

It is a junction number, because it is equal to n+sod(n) for n = 21554331393 and 21554331402.

It is not an unprimeable number, because it can be changed into a prime (21554331439) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15483738 + ... + 15485129.

It is an arithmetic number, because the mean of its divisors is an integer number (1741998825).

Almost surely, 2^21554331432 is an apocalyptic number.

It is an amenable number.

21554331432 is an abundant number, since it is smaller than the sum of its proper divisors (34189630968).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21554331432 is a wasteful number, since it uses less digits than its factorization.

21554331432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30968905 (or 30968901 counting only the distinct ones).

The product of its digits is 43200, while the sum is 33.

Adding to 21554331432 its reverse (23413345512), we get a palindrome (44967676944).

The spelling of 21554331432 in words is "twenty-one billion, five hundred fifty-four million, three hundred thirty-one thousand, four hundred thirty-two".