21040505488 has 40 divisors (see below), whose sum is σ = 42194620800. Its totient is φ = 10151965824.

The previous prime is 21040505461. The next prime is 21040505489. The reversal of 21040505488 is 88450504012.

It is not an unprimeable number, because it can be changed into a prime (21040505489) 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, 918073 + ... + 940711.

It is an arithmetic number, because the mean of its divisors is an integer number (1054865520).

Almost surely, 2^21040505488 is an apocalyptic number.

It is an amenable number.

21040505488 is an abundant number, since it is smaller than the sum of its proper divisors (21154115312).

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

21040505488 is a wasteful number, since it uses less digits than its factorization.

21040505488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24679 (or 24673 counting only the distinct ones).

The product of its (nonzero) digits is 51200, while the sum is 37.

The spelling of 21040505488 in words is "twenty-one billion, forty million, five hundred five thousand, four hundred eighty-eight".