2155951215709 has 2 divisors, whose sum is σ = 2155951215710. Its totient is φ = 2155951215708.

The previous prime is 2155951215637. The next prime is 2155951215773. The reversal of 2155951215709 is 9075121595512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1419426811609 + 736524404100 = 1191397^2 + 858210^2 .

It is a cyclic number.

It is not a de Polignac number, because 2155951215709 - 2⁷ = 2155951215581 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2155951215779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1077975607854 + 1077975607855.

It is an arithmetic number, because the mean of its divisors is an integer number (1077975607855).

Almost surely, 2^{2155951215709} is an apocalyptic number.

It is an amenable number.

2155951215709 is a deficient number, since it is larger than the sum of its proper divisors (1).

2155951215709 is an equidigital number, since it uses as much as digits as its factorization.

2155951215709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1417500, while the sum is 52.

The spelling of 2155951215709 in words is "two trillion, one hundred fifty-five billion, nine hundred fifty-one million, two hundred fifteen thousand, seven hundred nine".