31020223199981 has 2 divisors, whose sum is σ = 31020223199982. Its totient is φ = 31020223199980.

The previous prime is 31020223199951. The next prime is 31020223200077. The reversal of 31020223199981 is 18999132202013.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 29749115775625 + 1271107424356 = 5454275^2 + 1127434^2 .

It is a cyclic number.

It is not a de Polignac number, because 31020223199981 - 2³⁴ = 31003043330797 is a prime.

It is a super-2 number, since 2×31020223199981² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31020223199951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15510111599990 + 15510111599991.

It is an arithmetic number, because the mean of its divisors is an integer number (15510111599991).

Almost surely, 2^{31020223199981} is an apocalyptic number.

It is an amenable number.

31020223199981 is a deficient number, since it is larger than the sum of its proper divisors (1).

31020223199981 is an equidigital number, since it uses as much as digits as its factorization.

31020223199981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 419904, while the sum is 50.

The spelling of 31020223199981 in words is "thirty-one trillion, twenty billion, two hundred twenty-three million, one hundred ninety-nine thousand, nine hundred eighty-one".