261650625 has 20 divisors (see below), whose sum is σ = 435947952. Its totient is φ = 139546000.

The previous prime is 261650603. The next prime is 261650639. The reversal of 261650625 is 526056162.

It is a happy number.

261650625 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 261650625 - 2⁵ = 261650593 is a prime.

It is a super-2 number, since 2×261650625² = 136922099125781250, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 67899 + ... + 71648.

Almost surely, 2^261650625 is an apocalyptic number.

261650625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

261650625 is a deficient number, since it is larger than the sum of its proper divisors (174297327).

261650625 is an equidigital number, since it uses as much as digits as its factorization.

261650625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139570 (or 139555 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 261650625 is about 16175.6182262070. The cubic root of 261650625 is about 639.5982382429.

The spelling of 261650625 in words is "two hundred sixty-one million, six hundred fifty thousand, six hundred twenty-five".