21405346020250 has 64 divisors (see below), whose sum is σ = 41069774831904. Its totient is φ = 8348904000000.

The previous prime is 21405346020239. The next prime is 21405346020287. The reversal of 21405346020250 is 5202064350412.

It can be written as a sum of positive squares in 16 ways, for example, as 16873092489969 + 4532253530281 = 4107687^2 + 2128909^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 18935980 + ... + 20034520.

Almost surely, 2^{21405346020250} is an apocalyptic number.

21405346020250 is a deficient number, since it is larger than the sum of its proper divisors (19664428811654).

21405346020250 is a wasteful number, since it uses less digits than its factorization.

21405346020250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100500 (or 1100490 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 34.

The spelling of 21405346020250 in words is "twenty-one trillion, four hundred five billion, three hundred forty-six million, twenty thousand, two hundred fifty".