261957492 has 18 divisors (see below), whose sum is σ = 662170418. Its totient is φ = 87319152.

The previous prime is 261957469. The next prime is 261957497. The reversal of 261957492 is 294759162.

It can be written as a sum of positive squares in only one way, i.e., 259725456 + 2232036 = 16116^2 + 1494^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a super-2 number, since 2×261957492² = 137243455229860128, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261957497) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3638263 + ... + 3638334.

Almost surely, 2^261957492 is an apocalyptic number.

It is an amenable number.

261957492 is an abundant number, since it is smaller than the sum of its proper divisors (400212926).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261957492 is a wasteful number, since it uses less digits than its factorization.

261957492 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7276607 (or 7276602 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 261957492 is about 16185.1009264694. The cubic root of 261957492 is about 639.8481833909.

The spelling of 261957492 in words is "two hundred sixty-one million, nine hundred fifty-seven thousand, four hundred ninety-two".