20347190681 has 2 divisors, whose sum is σ = 20347190682. Its totient is φ = 20347190680.

The previous prime is 20347190641. The next prime is 20347190693. The reversal of 20347190681 is 18609174302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20005273600 + 341917081 = 141440^2 + 18491^2 .

It is a cyclic number.

It is not a de Polignac number, because 20347190681 - 2²⁶ = 20280081817 is a prime.

It is a super-2 number, since 2×20347190681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20347190641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10173595340 + 10173595341.

It is an arithmetic number, because the mean of its divisors is an integer number (10173595341).

Almost surely, 2^20347190681 is an apocalyptic number.

It is an amenable number.

20347190681 is a deficient number, since it is larger than the sum of its proper divisors (1).

20347190681 is an equidigital number, since it uses as much as digits as its factorization.

20347190681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 41.

The spelling of 20347190681 in words is "twenty billion, three hundred forty-seven million, one hundred ninety thousand, six hundred eighty-one".