21021423410 has 32 divisors (see below), whose sum is σ = 40817174832. Its totient is φ = 7748812800.

The previous prime is 21021423383. The next prime is 21021423421. The reversal of 21021423410 is 1432412012.

It can be written as a sum of positive squares in 8 ways, for example, as 5311057129 + 15710366281 = 72877^2 + 125341^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56399 + ... + 212658.

Almost surely, 2^21021423410 is an apocalyptic number.

21021423410 is a deficient number, since it is larger than the sum of its proper divisors (19795751422).

21021423410 is a wasteful number, since it uses less digits than its factorization.

21021423410 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 269678.

The product of its (nonzero) digits is 384, while the sum is 20.

Adding to 21021423410 its reverse (1432412012), we get a palindrome (22453835422).

The spelling of 21021423410 in words is "twenty-one billion, twenty-one million, four hundred twenty-three thousand, four hundred ten".