203131110013721 has 2 divisors, whose sum is σ = 203131110013722. Its totient is φ = 203131110013720.

The previous prime is 203131110013709. The next prime is 203131110013787. The reversal of 203131110013721 is 127310011131302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196443770905600 + 6687339108121 = 14015840^2 + 2585989^2 .

It is a cyclic number.

It is not a de Polignac number, because 203131110013721 - 2²⁶ = 203131042904857 is a prime.

It is not a weakly prime, because it can be changed into another prime (203131110010721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101565555006860 + 101565555006861.

It is an arithmetic number, because the mean of its divisors is an integer number (101565555006861).

Almost surely, 2^{203131110013721} is an apocalyptic number.

It is an amenable number.

203131110013721 is a deficient number, since it is larger than the sum of its proper divisors (1).

203131110013721 is an equidigital number, since it uses as much as digits as its factorization.

203131110013721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 756, while the sum is 26.

The spelling of 203131110013721 in words is "two hundred three trillion, one hundred thirty-one billion, one hundred ten million, thirteen thousand, seven hundred twenty-one".