31221001433477 has 2 divisors, whose sum is σ = 31221001433478. Its totient is φ = 31221001433476.

The previous prime is 31221001433471. The next prime is 31221001433527. The reversal of 31221001433477 is 77433410012213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20211552267076 + 11009449166401 = 4495726^2 + 3318049^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31221001433477 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31221001433477.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31221001433471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15610500716738 + 15610500716739.

It is an arithmetic number, because the mean of its divisors is an integer number (15610500716739).

Almost surely, 2^{31221001433477} is an apocalyptic number.

It is an amenable number.

31221001433477 is a deficient number, since it is larger than the sum of its proper divisors (1).

31221001433477 is an equidigital number, since it uses as much as digits as its factorization.

31221001433477 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 84672, while the sum is 38.

The spelling of 31221001433477 in words is "thirty-one trillion, two hundred twenty-one billion, one million, four hundred thirty-three thousand, four hundred seventy-seven".