381776702821 has 4 divisors (see below), whose sum is σ = 382255720812. Its totient is φ = 381297684832.

The previous prime is 381776702761. The next prime is 381776702833. The reversal of 381776702821 is 128207677183.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 128207677183 = 241 ⋅531982063.

It can be written as a sum of positive squares in 2 ways, for example, as 215561489796 + 166215213025 = 464286^2 + 407695^2 .

It is a cyclic number.

It is not a de Polignac number, because 381776702821 - 2³⁷ = 244337749349 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 (381776702851) 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, 239507800 + ... + 239509393.

It is an arithmetic number, because the mean of its divisors is an integer number (95563930203).

Almost surely, 2^381776702821 is an apocalyptic number.

It is an amenable number.

381776702821 is a deficient number, since it is larger than the sum of its proper divisors (479017991).

381776702821 is an equidigital number, since it uses as much as digits as its factorization.

381776702821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 479017990.

The product of its (nonzero) digits is 1580544, while the sum is 52.

The spelling of 381776702821 in words is "three hundred eighty-one billion, seven hundred seventy-six million, seven hundred two thousand, eight hundred twenty-one".