31072509421 has 2 divisors, whose sum is σ = 31072509422. Its totient is φ = 31072509420.

The previous prime is 31072509401. The next prime is 31072509431. The reversal of 31072509421 is 12490527013.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19653236100 + 11419273321 = 140190^2 + 106861^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31072509421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31072509401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15536254710 + 15536254711.

It is an arithmetic number, because the mean of its divisors is an integer number (15536254711).

Almost surely, 2^31072509421 is an apocalyptic number.

It is an amenable number.

31072509421 is a deficient number, since it is larger than the sum of its proper divisors (1).

31072509421 is an equidigital number, since it uses as much as digits as its factorization.

31072509421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 34.

The spelling of 31072509421 in words is "thirty-one billion, seventy-two million, five hundred nine thousand, four hundred twenty-one".