25666149193 has 4 divisors (see below), whose sum is σ = 25862074128. Its totient is φ = 25470224260.

The previous prime is 25666149181. The next prime is 25666149203. The reversal of 25666149193 is 39194166652.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 25666149193 - 2²⁵ = 25632594761 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25666149193.

It is not an unprimeable number, because it can be changed into a prime (25666149163) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97962271 + ... + 97962532.

It is an arithmetic number, because the mean of its divisors is an integer number (6465518532).

Almost surely, 2^25666149193 is an apocalyptic number.

It is an amenable number.

25666149193 is a deficient number, since it is larger than the sum of its proper divisors (195924935).

25666149193 is a wasteful number, since it uses less digits than its factorization.

25666149193 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195924934.

The product of its digits is 2099520, while the sum is 52.

The spelling of 25666149193 in words is "twenty-five billion, six hundred sixty-six million, one hundred forty-nine thousand, one hundred ninety-three".