261554106714520 has 32 divisors (see below), whose sum is σ = 614083554897120. Its totient is φ = 100072875612160.

The previous prime is 261554106714517. The next prime is 261554106714559. The reversal of 261554106714520 is 25417601455162.

It is a happy number.

It is a super-2 number, since 2×261554106714520² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 142148970121 + ... + 142148971960.

It is an arithmetic number, because the mean of its divisors is an integer number (19190111090535).

Almost surely, 2^{261554106714520} is an apocalyptic number.

261554106714520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261554106714520 is an abundant number, since it is smaller than the sum of its proper divisors (352529448182600).

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

261554106714520 is a wasteful number, since it uses less digits than its factorization.

261554106714520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 284297942115 (or 284297942111 counting only the distinct ones).

The product of its (nonzero) digits is 2016000, while the sum is 49.

The spelling of 261554106714520 in words is "two hundred sixty-one trillion, five hundred fifty-four billion, one hundred six million, seven hundred fourteen thousand, five hundred twenty".