100405256261 has 8 divisors (see below), whose sum is σ = 100532058264. Its totient is φ = 100278501120.

The previous prime is 100405256257. The next prime is 100405256279. The reversal of 100405256261 is 162652504001.

It can be written as a sum of positive squares in 4 ways, for example, as 56225420161 + 44179836100 = 237119^2 + 210190^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 100405256261 - 2² = 100405256257 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100405256251) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6340025 + ... + 6355841.

It is an arithmetic number, because the mean of its divisors is an integer number (12566507283).

Almost surely, 2^100405256261 is an apocalyptic number.

It is an amenable number.

100405256261 is a deficient number, since it is larger than the sum of its proper divisors (126802003).

100405256261 is an equidigital number, since it uses as much as digits as its factorization.

100405256261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23431.

The product of its (nonzero) digits is 14400, while the sum is 32.

The spelling of 100405256261 in words is "one hundred billion, four hundred five million, two hundred fifty-six thousand, two hundred sixty-one".