20715418421 has 4 divisors (see below), whose sum is σ = 20718319200. Its totient is φ = 20712517644.

The previous prime is 20715418369. The next prime is 20715418501. The reversal of 20715418421 is 12481451702.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20715418421 - 2¹⁰ = 20715417397 is a prime.

It is a super-2 number, since 2×20715418421² (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 (20715118421) 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, 1439651 + ... + 1453968.

It is an arithmetic number, because the mean of its divisors is an integer number (5179579800).

Almost surely, 2^20715418421 is an apocalyptic number.

It is an amenable number.

20715418421 is a deficient number, since it is larger than the sum of its proper divisors (2900779).

20715418421 is an equidigital number, since it uses as much as digits as its factorization.

20715418421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2900778.

The product of its (nonzero) digits is 17920, while the sum is 35.

The spelling of 20715418421 in words is "twenty billion, seven hundred fifteen million, four hundred eighteen thousand, four hundred twenty-one".