25978157 has 2 divisors, whose sum is σ = 25978158. Its totient is φ = 25978156.

The previous prime is 25978153. The next prime is 25978163. The reversal of 25978157 is 75187952.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21771556 + 4206601 = 4666^2 + 2051^2 .

It is a cyclic number.

It is not a de Polignac number, because 25978157 - 2² = 25978153 is a prime.

It is a super-2 number, since 2×25978157² = 1349729282233298, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25978153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12989078 + 12989079.

It is an arithmetic number, because the mean of its divisors is an integer number (12989079).

Almost surely, 2^25978157 is an apocalyptic number.

It is an amenable number.

25978157 is a deficient number, since it is larger than the sum of its proper divisors (1).

25978157 is an equidigital number, since it uses as much as digits as its factorization.

25978157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 176400, while the sum is 44.

The square root of 25978157 is about 5096.8771811767. The cubic root of 25978157 is about 296.1666223134.

The spelling of 25978157 in words is "twenty-five million, nine hundred seventy-eight thousand, one hundred fifty-seven".