261122553 has 12 divisors (see below), whose sum is σ = 385202688. Its totient is φ = 170377560.

The previous prime is 261122551. The next prime is 261122581. The reversal of 261122553 is 355221162.

It is a happy number.

It is not a de Polignac number, because 261122553 - 2¹ = 261122551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261122551) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 308233 + ... + 309078.

It is an arithmetic number, because the mean of its divisors is an integer number (32100224).

Almost surely, 2^261122553 is an apocalyptic number.

It is an amenable number.

261122553 is a deficient number, since it is larger than the sum of its proper divisors (124080135).

261122553 is a wasteful number, since it uses less digits than its factorization.

261122553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 617364 (or 617361 counting only the distinct ones).

The product of its digits is 3600, while the sum is 27.

The square root of 261122553 is about 16159.2868963949. The cubic root of 261122553 is about 639.1676622944.

The spelling of 261122553 in words is "two hundred sixty-one million, one hundred twenty-two thousand, five hundred fifty-three".