21340022051 has 4 divisors (see below), whose sum is σ = 21701717400. Its totient is φ = 20978326704.

The previous prime is 21340022027. The next prime is 21340022087. The reversal of 21340022051 is 15022004312.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21340022051 is a prime.

It is a super-2 number, since 2×21340022051² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21340022251) 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, 180847586 + ... + 180847703.

It is an arithmetic number, because the mean of its divisors is an integer number (5425429350).

Almost surely, 2^21340022051 is an apocalyptic number.

21340022051 is a deficient number, since it is larger than the sum of its proper divisors (361695349).

21340022051 is an equidigital number, since it uses as much as digits as its factorization.

21340022051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361695348.

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 21340022051 its reverse (15022004312), we get a palindrome (36362026363).

The spelling of 21340022051 in words is "twenty-one billion, three hundred forty million, twenty-two thousand, fifty-one".