261038749 has 4 divisors (see below), whose sum is σ = 261309664. Its totient is φ = 260767836.

The previous prime is 261038747. The next prime is 261038797. The reversal of 261038749 is 947830162.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 261038749 - 2¹ = 261038747 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 (261038747) 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, 134007 + ... + 135940.

It is an arithmetic number, because the mean of its divisors is an integer number (65327416).

Almost surely, 2^261038749 is an apocalyptic number.

It is an amenable number.

261038749 is a deficient number, since it is larger than the sum of its proper divisors (270915).

261038749 is an equidigital number, since it uses as much as digits as its factorization.

261038749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 270914.

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 261038749 is about 16156.6936283387. The cubic root of 261038749 is about 639.0992773701.

The spelling of 261038749 in words is "two hundred sixty-one million, thirty-eight thousand, seven hundred forty-nine".