21511244552 has 32 divisors (see below), whose sum is σ = 46120000320. Its totient is φ = 9214209600.

The previous prime is 21511244509. The next prime is 21511244563. The reversal of 21511244552 is 25544211512.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5423 + ... + 207489.

It is an arithmetic number, because the mean of its divisors is an integer number (1441250010).

Almost surely, 2^21511244552 is an apocalyptic number.

It is an amenable number.

21511244552 is an abundant number, since it is smaller than the sum of its proper divisors (24608755768).

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

21511244552 is a wasteful number, since it uses less digits than its factorization.

21511244552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203981 (or 203977 counting only the distinct ones).

The product of its digits is 16000, while the sum is 32.

The spelling of 21511244552 in words is "twenty-one billion, five hundred eleven million, two hundred forty-four thousand, five hundred fifty-two".