20451722231 has 2 divisors, whose sum is σ = 20451722232. Its totient is φ = 20451722230.

The previous prime is 20451722197. The next prime is 20451722243. The reversal of 20451722231 is 13222715402.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20451722231 - 2⁶ = 20451722167 is a prime.

It is a super-2 number, since 2×20451722231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20451722194 and 20451722203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20451722261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10225861115 + 10225861116.

It is an arithmetic number, because the mean of its divisors is an integer number (10225861116).

Almost surely, 2^20451722231 is an apocalyptic number.

20451722231 is a deficient number, since it is larger than the sum of its proper divisors (1).

20451722231 is an equidigital number, since it uses as much as digits as its factorization.

20451722231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6720, while the sum is 29.

The spelling of 20451722231 in words is "twenty billion, four hundred fifty-one million, seven hundred twenty-two thousand, two hundred thirty-one".