21351662450 has 48 divisors (see below), whose sum is σ = 41705098560. Its totient is φ = 8117229120.

The previous prime is 21351662419. The next prime is 21351662491. The reversal of 21351662450 is 5426615312.

It is a self number, because there is not a number n which added to its sum of digits gives 21351662450.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 121421 + ... + 239679.

It is an arithmetic number, because the mean of its divisors is an integer number (868856220).

Almost surely, 2^21351662450 is an apocalyptic number.

21351662450 is a deficient number, since it is larger than the sum of its proper divisors (20353436110).

21351662450 is a wasteful number, since it uses less digits than its factorization.

21351662450 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118451 (or 118446 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 35.

The spelling of 21351662450 in words is "twenty-one billion, three hundred fifty-one million, six hundred sixty-two thousand, four hundred fifty".