15195962921 has 2 divisors, whose sum is σ = 15195962922. Its totient is φ = 15195962920.

The previous prime is 15195962843. The next prime is 15195962923. The reversal of 15195962921 is 12926959151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11792874025 + 3403088896 = 108595^2 + 58336^2 .

It is a cyclic number.

It is not a de Polignac number, because 15195962921 - 2¹⁴ = 15195946537 is a prime.

It is a Sophie Germain prime.

Together with 15195962923, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 15195962921.

It is not a weakly prime, because it can be changed into another prime (15195962923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7597981460 + 7597981461.

It is an arithmetic number, because the mean of its divisors is an integer number (7597981461).

Almost surely, 2^15195962921 is an apocalyptic number.

It is an amenable number.

15195962921 is a deficient number, since it is larger than the sum of its proper divisors (1).

15195962921 is an equidigital number, since it uses as much as digits as its factorization.

15195962921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 437400, while the sum is 50.

The spelling of 15195962921 in words is "fifteen billion, one hundred ninety-five million, nine hundred sixty-two thousand, nine hundred twenty-one".