21531263162 has 4 divisors (see below), whose sum is σ = 32296894746. Its totient is φ = 10765631580.

The previous prime is 21531263153. The next prime is 21531263189. The reversal of 21531263162 is 26136213512.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15428372521 + 6102890641 = 124211^2 + 78121^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5382815789 + ... + 5382815792.

Almost surely, 2^21531263162 is an apocalyptic number.

21531263162 is a deficient number, since it is larger than the sum of its proper divisors (10765631584).

21531263162 is a wasteful number, since it uses less digits than its factorization.

21531263162 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10765631583.

The product of its digits is 12960, while the sum is 32.

Adding to 21531263162 its reverse (26136213512), we get a palindrome (47667476674).

The spelling of 21531263162 in words is "twenty-one billion, five hundred thirty-one million, two hundred sixty-three thousand, one hundred sixty-two".