261291274 has 4 divisors (see below), whose sum is σ = 391936914. Its totient is φ = 130645636.

The previous prime is 261291271. The next prime is 261291311. The reversal of 261291274 is 472192162.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 252333225 + 8958049 = 15885^2 + 2993^2 .

It is not an unprimeable number, because it can be changed into a prime (261291271) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65322817 + ... + 65322820.

Almost surely, 2^261291274 is an apocalyptic number.

261291274 is a deficient number, since it is larger than the sum of its proper divisors (130645640).

261291274 is a wasteful number, since it uses less digits than its factorization.

261291274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130645639.

The product of its digits is 12096, while the sum is 34.

The square root of 261291274 is about 16164.5066117095. The cubic root of 261291274 is about 639.3052959937.

The spelling of 261291274 in words is "two hundred sixty-one million, two hundred ninety-one thousand, two hundred seventy-four".