261940437 has 36 divisors (see below), whose sum is σ = 440376300. Its totient is φ = 149402880.

The previous prime is 261940429. The next prime is 261940451. The reversal of 261940437 is 734049162.

261940437 is a `hidden beast` number, since 2 + 619 + 4 + 0 + 4 + 37 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 227436561 + 34503876 = 15081^2 + 5874^2 .

It is not a de Polignac number, because 261940437 - 2³ = 261940429 is a prime.

It is a super-2 number, since 2×261940437² = 137225585071501938, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261940487) 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 35 ways as a sum of consecutive naturals, for example, 11439 + ... + 25587.

It is an arithmetic number, because the mean of its divisors is an integer number (12232675).

Almost surely, 2^261940437 is an apocalyptic number.

It is an amenable number.

261940437 is a deficient number, since it is larger than the sum of its proper divisors (178435863).

261940437 is a wasteful number, since it uses less digits than its factorization.

261940437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14194 (or 14180 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 36.

The square root of 261940437 is about 16184.5740444412. The cubic root of 261940437 is about 639.8342971079.

Adding to 261940437 its reverse (734049162), we get a palindrome (995989599).

The spelling of 261940437 in words is "two hundred sixty-one million, nine hundred forty thousand, four hundred thirty-seven".