31761472381 has 2 divisors, whose sum is σ = 31761472382. Its totient is φ = 31761472380.

The previous prime is 31761472367. The next prime is 31761472429. The reversal of 31761472381 is 18327416713.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 31696105156 + 65367225 = 178034^2 + 8085^2 .

It is an emirp because it is prime and its reverse (18327416713) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 31761472381 - 2⁵ = 31761472349 is a prime.

It is a super-2 number, since 2×31761472381² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31761472331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15880736190 + 15880736191.

It is an arithmetic number, because the mean of its divisors is an integer number (15880736191).

Almost surely, 2^31761472381 is an apocalyptic number.

It is an amenable number.

31761472381 is a deficient number, since it is larger than the sum of its proper divisors (1).

31761472381 is an equidigital number, since it uses as much as digits as its factorization.

31761472381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 169344, while the sum is 43.

The spelling of 31761472381 in words is "thirty-one billion, seven hundred sixty-one million, four hundred seventy-two thousand, three hundred eighty-one".