261926751 has 4 divisors (see below), whose sum is σ = 349235672. Its totient is φ = 174617832.

The previous prime is 261926699. The next prime is 261926767. The reversal of 261926751 is 157629162.

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

It is a de Polignac number, because none of the positive numbers 2^k-261926751 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261916751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43654456 + ... + 43654461.

It is an arithmetic number, because the mean of its divisors is an integer number (87308918).

Almost surely, 2^261926751 is an apocalyptic number.

261926751 is a deficient number, since it is larger than the sum of its proper divisors (87308921).

261926751 is an equidigital number, since it uses as much as digits as its factorization.

261926751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87308920.

The product of its digits is 45360, while the sum is 39.

The square root of 261926751 is about 16184.1512289029. The cubic root of 261926751 is about 639.8231534490.

The spelling of 261926751 in words is "two hundred sixty-one million, nine hundred twenty-six thousand, seven hundred fifty-one".