261296144501520 has 80 divisors (see below), whose sum is σ = 810024059160000. Its totient is φ = 69678454774272.

The previous prime is 261296144501503. The next prime is 261296144501617. The reversal of 261296144501520 is 25105441692162.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 261296144501520.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28927231 + ... + 36869729.

It is an arithmetic number, because the mean of its divisors is an integer number (10125300739500).

Almost surely, 2^{261296144501520} is an apocalyptic number.

261296144501520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261296144501520 is an abundant number, since it is smaller than the sum of its proper divisors (548727914658480).

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

261296144501520 is a wasteful number, since it uses less digits than its factorization.

261296144501520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8079592 (or 8079586 counting only the distinct ones).

The product of its (nonzero) digits is 1036800, while the sum is 48.

The spelling of 261296144501520 in words is "two hundred sixty-one trillion, two hundred ninety-six billion, one hundred forty-four million, five hundred one thousand, five hundred twenty".