381821652921 has 16 divisors (see below), whose sum is σ = 526363992000. Its totient is φ = 246005886528.

The previous prime is 381821652857. The next prime is 381821652923. The reversal of 381821652921 is 129256128183.

It is not a de Polignac number, because 381821652921 - 2⁶ = 381821652857 is a prime.

It is not an unprimeable number, because it can be changed into a prime (381821652923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11526531 + ... + 11559608.

It is an arithmetic number, because the mean of its divisors is an integer number (32897749500).

Almost surely, 2^381821652921 is an apocalyptic number.

It is an amenable number.

381821652921 is a deficient number, since it is larger than the sum of its proper divisors (144542339079).

381821652921 is a wasteful number, since it uses less digits than its factorization.

381821652921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23086328.

The product of its digits is 414720, while the sum is 48.

The spelling of 381821652921 in words is "three hundred eighty-one billion, eight hundred twenty-one million, six hundred fifty-two thousand, nine hundred twenty-one".