261434617899 has 32 divisors (see below), whose sum is σ = 431900313600. Its totient is φ = 136974056832.

The previous prime is 261434617883. The next prime is 261434617909. The reversal of 261434617899 is 998716434162.

It is not a de Polignac number, because 261434617899 - 2⁴ = 261434617883 is a prime.

It is a super-2 number, since 2×261434617899² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (261434617879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3172867 + ... + 3254220.

It is an arithmetic number, because the mean of its divisors is an integer number (13496884800).

Almost surely, 2^261434617899 is an apocalyptic number.

261434617899 is a deficient number, since it is larger than the sum of its proper divisors (170465695701).

261434617899 is a wasteful number, since it uses less digits than its factorization.

261434617899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6427259.

The product of its digits is 15676416, while the sum is 60.

The spelling of 261434617899 in words is "two hundred sixty-one billion, four hundred thirty-four million, six hundred seventeen thousand, eight hundred ninety-nine".