261682749 has 24 divisors (see below), whose sum is σ = 391732224. Its totient is φ = 168156000.

The previous prime is 261682723. The next prime is 261682769. The reversal of 261682749 is 947286162.

It is a happy number.

261682749 is a `hidden beast` number, since 2 + 616 + 8 + 27 + 4 + 9 = 666.

It is not a de Polignac number, because 261682749 - 2⁹ = 261682237 is a prime.

It is a super-2 number, since 2×261682749² = 136955722248394002, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261682769) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 73879 + ... + 77339.

It is an arithmetic number, because the mean of its divisors is an integer number (16322176).

Almost surely, 2^261682749 is an apocalyptic number.

It is an amenable number.

261682749 is a deficient number, since it is larger than the sum of its proper divisors (130049475).

261682749 is a wasteful number, since it uses less digits than its factorization.

261682749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3769 (or 3766 counting only the distinct ones).

The product of its digits is 290304, while the sum is 45.

The square root of 261682749 is about 16176.6111716886. The cubic root of 261682749 is about 639.6244126029.

The spelling of 261682749 in words is "two hundred sixty-one million, six hundred eighty-two thousand, seven hundred forty-nine".