20642302421 has 4 divisors (see below), whose sum is σ = 22230171852. Its totient is φ = 19054432992.

The previous prime is 20642302403. The next prime is 20642302441. The reversal of 20642302421 is 12420324602.

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 2 ways, for example, as 4458900625 + 16183401796 = 66775^2 + 127214^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20642302421 is a prime.

It is a super-2 number, since 2×20642302421² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20642302441) 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, 793934696 + ... + 793934721.

It is an arithmetic number, because the mean of its divisors is an integer number (5557542963).

Almost surely, 2^20642302421 is an apocalyptic number.

It is an amenable number.

20642302421 is a deficient number, since it is larger than the sum of its proper divisors (1587869431).

20642302421 is a wasteful number, since it uses less digits than its factorization.

20642302421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1587869430.

The product of its (nonzero) digits is 4608, while the sum is 26.

The spelling of 20642302421 in words is "twenty billion, six hundred forty-two million, three hundred two thousand, four hundred twenty-one".