21343572634 has 4 divisors (see below), whose sum is σ = 32015358954. Its totient is φ = 10671786316.

The previous prime is 21343572617. The next prime is 21343572659. The reversal of 21343572634 is 43627534312.

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., 17073342225 + 4270230409 = 130665^2 + 65347^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5335893157 + ... + 5335893160.

Almost surely, 2^21343572634 is an apocalyptic number.

21343572634 is a deficient number, since it is larger than the sum of its proper divisors (10671786320).

21343572634 is a wasteful number, since it uses less digits than its factorization.

21343572634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10671786319.

The product of its digits is 362880, while the sum is 40.

The spelling of 21343572634 in words is "twenty-one billion, three hundred forty-three million, five hundred seventy-two thousand, six hundred thirty-four".