21450420364 has 24 divisors (see below), whose sum is σ = 39005797376. Its totient is φ = 10310490000.

The previous prime is 21450420359. The next prime is 21450420371. The reversal of 21450420364 is 46302405412.

It is a Harshad number since it is a multiple of its sum of digits (31).

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, 554082 + ... + 591529.

Almost surely, 2^21450420364 is an apocalyptic number.

It is an amenable number.

21450420364 is a deficient number, since it is larger than the sum of its proper divisors (17555377012).

21450420364 is a wasteful number, since it uses less digits than its factorization.

21450420364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1145797 (or 1145795 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 31.

Adding to 21450420364 its reverse (46302405412), we get a palindrome (67752825776).

The spelling of 21450420364 in words is "twenty-one billion, four hundred fifty million, four hundred twenty thousand, three hundred sixty-four".