261724874 has 4 divisors (see below), whose sum is σ = 392587314. Its totient is φ = 130862436.

The previous prime is 261724873. The next prime is 261724891. The reversal of 261724874 is 478427162.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 478427162 = 2 ⋅239213581.

It can be written as a sum of positive squares in only one way, i.e., 261630625 + 94249 = 16175^2 + 307^2 .

It is not an unprimeable number, because it can be changed into a prime (261724873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65431217 + ... + 65431220.

Almost surely, 2^261724874 is an apocalyptic number.

261724874 is a deficient number, since it is larger than the sum of its proper divisors (130862440).

261724874 is a wasteful number, since it uses less digits than its factorization.

261724874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130862439.

The product of its digits is 150528, while the sum is 41.

The square root of 261724874 is about 16177.9131534324. The cubic root of 261724874 is about 639.6587324461.

The spelling of 261724874 in words is "two hundred sixty-one million, seven hundred twenty-four thousand, eight hundred seventy-four".