21371230733 has 4 divisors (see below), whose sum is σ = 21567297180. Its totient is φ = 21175164288.

The previous prime is 21371230711. The next prime is 21371230753. The reversal of 21371230733 is 33703217312.

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

It can be written as a sum of positive squares in 2 ways, for example, as 13242946084 + 8128284649 = 115078^2 + 90157^2 .

It is a cyclic number.

It is not a de Polignac number, because 21371230733 - 2¹² = 21371226637 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21371230733.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21371230753) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98033060 + ... + 98033277.

It is an arithmetic number, because the mean of its divisors is an integer number (5391824295).

Almost surely, 2^21371230733 is an apocalyptic number.

It is an amenable number.

21371230733 is a deficient number, since it is larger than the sum of its proper divisors (196066447).

21371230733 is a wasteful number, since it uses less digits than its factorization.

21371230733 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196066446.

The product of its (nonzero) digits is 15876, while the sum is 32.

The spelling of 21371230733 in words is "twenty-one billion, three hundred seventy-one million, two hundred thirty thousand, seven hundred thirty-three".