25217687209 has 64 divisors (see below), whose sum is σ = 32107622400. Its totient is φ = 19466092800.

The previous prime is 25217687189. The next prime is 25217687213. The reversal of 25217687209 is 90278671252.

It is not a de Polignac number, because 25217687209 - 2⁷ = 25217687081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25217687279) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 39964324 + ... + 39964954.

It is an arithmetic number, because the mean of its divisors is an integer number (501681600).

Almost surely, 2^25217687209 is an apocalyptic number.

25217687209 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

It is an amenable number.

25217687209 is a deficient number, since it is larger than the sum of its proper divisors (6889935191).

25217687209 is a wasteful number, since it uses less digits than its factorization.

25217687209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1126.

The product of its (nonzero) digits is 846720, while the sum is 49.

The spelling of 25217687209 in words is "twenty-five billion, two hundred seventeen million, six hundred eighty-seven thousand, two hundred nine".