21311432402 has 16 divisors (see below), whose sum is σ = 34443312792. Its totient is φ = 9831144960.

The previous prime is 21311432377. The next prime is 21311432431. The reversal of 21311432402 is 20423411312.

It can be written as a sum of positive squares in 4 ways, for example, as 11295225841 + 10016206561 = 106279^2 + 100081^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 150749 + ... + 255632.

Almost surely, 2^21311432402 is an apocalyptic number.

21311432402 is a deficient number, since it is larger than the sum of its proper divisors (13131880390).

21311432402 is a wasteful number, since it uses less digits than its factorization.

21311432402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 408413.

The product of its (nonzero) digits is 1152, while the sum is 23.

Adding to 21311432402 its reverse (20423411312), we get a palindrome (41734843714).

The spelling of 21311432402 in words is "twenty-one billion, three hundred eleven million, four hundred thirty-two thousand, four hundred two".