261510687400 has 48 divisors (see below), whose sum is σ = 608136300000. Its totient is φ = 104582950080.

The previous prime is 261510687371. The next prime is 261510687443. The reversal of 261510687400 is 4786015162.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 869019 + ... + 1130581.

It is an arithmetic number, because the mean of its divisors is an integer number (12669506250).

Almost surely, 2^261510687400 is an apocalyptic number.

261510687400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261510687400 is an abundant number, since it is smaller than the sum of its proper divisors (346625612600).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

261510687400 is a wasteful number, since it uses less digits than its factorization.

261510687400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266578 (or 266569 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 40.

The spelling of 261510687400 in words is "two hundred sixty-one billion, five hundred ten million, six hundred eighty-seven thousand, four hundred".