25400861 has 4 divisors (see below), whose sum is σ = 25748892. Its totient is φ = 25052832.

The previous prime is 25400849. The next prime is 25400887. The reversal of 25400861 is 16800452.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5428900 + 19971961 = 2330^2 + 4469^2 .

It is a cyclic number.

It is not a de Polignac number, because 25400861 - 2⁶ = 25400797 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25400861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25400801) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 173906 + ... + 174051.

It is an arithmetic number, because the mean of its divisors is an integer number (6437223).

Almost surely, 2^25400861 is an apocalyptic number.

It is an amenable number.

25400861 is a deficient number, since it is larger than the sum of its proper divisors (348031).

25400861 is an equidigital number, since it uses as much as digits as its factorization.

25400861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348030.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 25400861 is about 5039.9266859747. The cubic root of 25400861 is about 293.9563272936.

The spelling of 25400861 in words is "twenty-five million, four hundred thousand, eight hundred sixty-one".