25181985 has 16 divisors (see below), whose sum is σ = 40472640. Its totient is φ = 13369920.

The previous prime is 25181983. The next prime is 25181993. The reversal of 25181985 is 58918152.

It is not a de Polignac number, because 25181985 - 2¹ = 25181983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (25181983) 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, 231 + ... + 7100.

It is an arithmetic number, because the mean of its divisors is an integer number (2529540).

Almost surely, 2^25181985 is an apocalyptic number.

It is an amenable number.

25181985 is a deficient number, since it is larger than the sum of its proper divisors (15290655).

25181985 is a wasteful number, since it uses less digits than its factorization.

25181985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7568.

The product of its digits is 28800, while the sum is 39.

The square root of 25181985 is about 5018.1655014557. The cubic root of 25181985 is about 293.1095623217.

The spelling of 25181985 in words is "twenty-five million, one hundred eighty-one thousand, nine hundred eighty-five".