25000081 has 8 divisors (see below), whose sum is σ = 26571240. Its totient is φ = 23440128.

The previous prime is 25000069. The next prime is 25000109. The reversal of 25000081 is 18000052.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 81 + 25000000 = 9^2 + 5000^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25000081 is a prime.

It is a super-2 number, since 2×25000081² = 1250008100013122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (25000681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2055 + ... + 7363.

It is an arithmetic number, because the mean of its divisors is an integer number (3321405).

Almost surely, 2^25000081 is an apocalyptic number.

It is an amenable number.

25000081 is a deficient number, since it is larger than the sum of its proper divisors (1571159).

25000081 is a wasteful number, since it uses less digits than its factorization.

25000081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5603.

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 25000081 is about 5000.0080999934. The cubic root of 25000081 is about 292.4020896149.

It can be divided in two parts, 250000 and 81, that multiplied together give a square (20250000 = 4500²).

The spelling of 25000081 in words is "twenty-five million, eighty-one", and thus it is an aban number and an uban number.