261115156 has 6 divisors (see below), whose sum is σ = 456951530. Its totient is φ = 130557576.

The previous prime is 261115109. The next prime is 261115163. The reversal of 261115156 is 651511162.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 205463556 + 55651600 = 14334^2 + 7460^2 .

It is a super-2 number, since 2×261115156² = 136362249385808672, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32639391 + ... + 32639398.

Almost surely, 2^261115156 is an apocalyptic number.

It is an amenable number.

261115156 is a deficient number, since it is larger than the sum of its proper divisors (195836374).

261115156 is a wasteful number, since it uses less digits than its factorization.

261115156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65278793 (or 65278791 counting only the distinct ones).

The product of its digits is 1800, while the sum is 28.

The square root of 261115156 is about 16159.0580170999. The cubic root of 261115156 is about 639.1616268553.

The spelling of 261115156 in words is "two hundred sixty-one million, one hundred fifteen thousand, one hundred fifty-six".