261145357 has 4 divisors (see below), whose sum is σ = 284885856. Its totient is φ = 237404860.

The previous prime is 261145349. The next prime is 261145369. The reversal of 261145357 is 753541162.

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 not a de Polignac number, because 261145357 - 2³ = 261145349 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 (261145327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11870233 + ... + 11870254.

It is an arithmetic number, because the mean of its divisors is an integer number (71221464).

Almost surely, 2^261145357 is an apocalyptic number.

It is an amenable number.

261145357 is a deficient number, since it is larger than the sum of its proper divisors (23740499).

261145357 is a wasteful number, since it uses less digits than its factorization.

261145357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23740498.

The product of its digits is 25200, while the sum is 34.

The square root of 261145357 is about 16159.9924814339. The cubic root of 261145357 is about 639.1862680601.

The spelling of 261145357 in words is "two hundred sixty-one million, one hundred forty-five thousand, three hundred fifty-seven".