261891152 has 20 divisors (see below), whose sum is σ = 507943680. Its totient is φ = 130808928.

The previous prime is 261891121. The next prime is 261891163. The reversal of 261891152 is 251198162.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8273 + ... + 24335.

It is an arithmetic number, because the mean of its divisors is an integer number (25397184).

Almost surely, 2^261891152 is an apocalyptic number.

It is an amenable number.

261891152 is a deficient number, since it is larger than the sum of its proper divisors (246052528).

261891152 is a wasteful number, since it uses less digits than its factorization.

261891152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17090 (or 17084 counting only the distinct ones).

The product of its digits is 8640, while the sum is 35.

The square root of 261891152 is about 16183.0513809973. The cubic root of 261891152 is about 639.7941655782.

The spelling of 261891152 in words is "two hundred sixty-one million, eight hundred ninety-one thousand, one hundred fifty-two".