25129999 has 2 divisors, whose sum is σ = 25130000. Its totient is φ = 25129998.

The previous prime is 25129981. The next prime is 25130011. The reversal of 25129999 is 99992152.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25129999 - 2⁹ = 25129487 is a prime.

25129999 is a modest number, since divided by 9999 gives 2512 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25129939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12564999 + 12565000.

It is an arithmetic number, because the mean of its divisors is an integer number (12565000).

Almost surely, 2^25129999 is an apocalyptic number.

25129999 is a deficient number, since it is larger than the sum of its proper divisors (1).

25129999 is an equidigital number, since it uses as much as digits as its factorization.

25129999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131220, while the sum is 46.

The square root of 25129999 is about 5012.9830440567. The cubic root of 25129999 is about 292.9077237016.

It can be divided in two parts, 25 and 129999, that multiplied together give a triangular number (3249975 = T₂₅₄₉).

The spelling of 25129999 in words is "twenty-five million, one hundred twenty-nine thousand, nine hundred ninety-nine".