261156455 has 16 divisors (see below), whose sum is σ = 370509120. Its totient is φ = 172902912.

The previous prime is 261156439. The next prime is 261156457. The reversal of 261156455 is 554651162.

It is not a de Polignac number, because 261156455 - 2⁴ = 261156439 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261156457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127634 + ... + 129663.

It is an arithmetic number, because the mean of its divisors is an integer number (23156820).

Almost surely, 2^261156455 is an apocalyptic number.

261156455 is a deficient number, since it is larger than the sum of its proper divisors (109352665).

261156455 is a wasteful number, since it uses less digits than its factorization.

261156455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 257338.

The product of its digits is 36000, while the sum is 35.

The square root of 261156455 is about 16160.3358566584. The cubic root of 261156455 is about 639.1953225177.

The spelling of 261156455 in words is "two hundred sixty-one million, one hundred fifty-six thousand, four hundred fifty-five".