261319245 has 16 divisors (see below), whose sum is σ = 456121152. Its totient is φ = 126700160.

The previous prime is 261319231. The next prime is 261319249. The reversal of 261319245 is 542913162.

It is not a de Polignac number, because 261319245 - 2¹⁵ = 261286477 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261319249) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 791712 + ... + 792041.

It is an arithmetic number, because the mean of its divisors is an integer number (28507572).

Almost surely, 2^261319245 is an apocalyptic number.

It is an amenable number.

261319245 is a deficient number, since it is larger than the sum of its proper divisors (194801907).

261319245 is a wasteful number, since it uses less digits than its factorization.

261319245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1583772.

The product of its digits is 12960, while the sum is 33.

The square root of 261319245 is about 16165.3717866308. The cubic root of 261319245 is about 639.3281075354.

The spelling of 261319245 in words is "two hundred sixty-one million, three hundred nineteen thousand, two hundred forty-five".