21420400132 has 12 divisors (see below), whose sum is σ = 37488361036. Its totient is φ = 10709439840.

The previous prime is 21420400093. The next prime is 21420400151. The reversal of 21420400132 is 23100402412.

It can be written as a sum of positive squares in 2 ways, for example, as 11181793536 + 10238606596 = 105744^2 + 101186^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124119 + ... + 241342.

Almost surely, 2^21420400132 is an apocalyptic number.

It is an amenable number.

21420400132 is a deficient number, since it is larger than the sum of its proper divisors (16067960904).

21420400132 is a wasteful number, since it uses less digits than its factorization.

21420400132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 380118 (or 380116 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21420400132 its reverse (23100402412), we get a palindrome (44520802544).

The spelling of 21420400132 in words is "twenty-one billion, four hundred twenty million, four hundred thousand, one hundred thirty-two".