100821046512785 has 4 divisors (see below), whose sum is σ = 120985255815348. Its totient is φ = 80656837210224.

The previous prime is 100821046512779. The next prime is 100821046512787. The reversal of 100821046512785 is 587215640128001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 66619696843921 + 34201349668864 = 8162089^2 + 5848192^2 .

It is a cyclic number.

It is not a de Polignac number, because 100821046512785 - 2²² = 100821042318481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (100821046512787) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10082104651274 + ... + 10082104651283.

It is an arithmetic number, because the mean of its divisors is an integer number (30246313953837).

Almost surely, 2^{100821046512785} is an apocalyptic number.

It is an amenable number.

100821046512785 is a deficient number, since it is larger than the sum of its proper divisors (20164209302563).

100821046512785 is an equidigital number, since it uses as much as digits as its factorization.

100821046512785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20164209302562.

The product of its (nonzero) digits is 1075200, while the sum is 50.

The spelling of 100821046512785 in words is "one hundred trillion, eight hundred twenty-one billion, forty-six million, five hundred twelve thousand, seven hundred eighty-five".