2157945193 has 2 divisors, whose sum is σ = 2157945194. Its totient is φ = 2157945192.

The previous prime is 2157945161. The next prime is 2157945199. The reversal of 2157945193 is 3915497512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2092788009 + 65157184 = 45747^2 + 8072^2 .

It is a cyclic number.

It is not a de Polignac number, because 2157945193 - 2⁵ = 2157945161 is a prime.

It is not a weakly prime, because it can be changed into another prime (2157945199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1078972596 + 1078972597.

It is an arithmetic number, because the mean of its divisors is an integer number (1078972597).

Almost surely, 2^2157945193 is an apocalyptic number.

It is an amenable number.

2157945193 is a deficient number, since it is larger than the sum of its proper divisors (1).

2157945193 is an equidigital number, since it uses as much as digits as its factorization.

2157945193 is an evil number, because the sum of its binary digits is even.

The product of its digits is 340200, while the sum is 46.

The square root of 2157945193 is about 46453.6886909963. The cubic root of 2157945193 is about 1292.2507814257.

The spelling of 2157945193 in words is "two billion, one hundred fifty-seven million, nine hundred forty-five thousand, one hundred ninety-three".