25719987 has 16 divisors (see below), whose sum is σ = 35546112. Its totient is φ = 16524960.

The previous prime is 25719983. The next prime is 25720001. The reversal of 25719987 is 78991752.

It is not a de Polignac number, because 25719987 - 2² = 25719983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25719983) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31873 + ... + 32669.

It is an arithmetic number, because the mean of its divisors is an integer number (2221632).

Almost surely, 2^25719987 is an apocalyptic number.

25719987 is a deficient number, since it is larger than the sum of its proper divisors (9826125).

25719987 is a wasteful number, since it uses less digits than its factorization.

25719987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178.

The product of its digits is 317520, while the sum is 48.

The square root of 25719987 is about 5071.4876515673. The cubic root of 25719987 is about 295.1822564265.

The spelling of 25719987 in words is "twenty-five million, seven hundred nineteen thousand, nine hundred eighty-seven".