99670756921 has 2 divisors, whose sum is σ = 99670756922. Its totient is φ = 99670756920.

The previous prime is 99670756891. The next prime is 99670756931. The reversal of 99670756921 is 12965707699.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 93639060025 + 6031696896 = 306005^2 + 77664^2 .

It is a cyclic number.

It is not a de Polignac number, because 99670756921 - 2¹³ = 99670748729 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 99670756921.

It is not a weakly prime, because it can be changed into another prime (99670756931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49835378460 + 49835378461.

It is an arithmetic number, because the mean of its divisors is an integer number (49835378461).

Almost surely, 2^99670756921 is an apocalyptic number.

It is an amenable number.

99670756921 is a deficient number, since it is larger than the sum of its proper divisors (1).

99670756921 is an equidigital number, since it uses as much as digits as its factorization.

99670756921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12859560, while the sum is 61.

The spelling of 99670756921 in words is "ninety-nine billion, six hundred seventy million, seven hundred fifty-six thousand, nine hundred twenty-one".