99681715157 has 2 divisors, whose sum is σ = 99681715158. Its totient is φ = 99681715156.

The previous prime is 99681715153. The next prime is 99681715171. The reversal of 99681715157 is 75151718699.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 88380749521 + 11300965636 = 297289^2 + 106306^2 .

It is a cyclic number.

It is not a de Polignac number, because 99681715157 - 2² = 99681715153 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 99681715096 and 99681715105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99681715153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49840857578 + 49840857579.

It is an arithmetic number, because the mean of its divisors is an integer number (49840857579).

Almost surely, 2^99681715157 is an apocalyptic number.

It is an amenable number.

99681715157 is a deficient number, since it is larger than the sum of its proper divisors (1).

99681715157 is an equidigital number, since it uses as much as digits as its factorization.

99681715157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4762800, while the sum is 59.

The spelling of 99681715157 in words is "ninety-nine billion, six hundred eighty-one million, seven hundred fifteen thousand, one hundred fifty-seven".