380401981 has 2 divisors, whose sum is σ = 380401982. Its totient is φ = 380401980.

The previous prime is 380401949. The next prime is 380401997. The reversal of 380401981 is 189104083.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 321879481 + 58522500 = 17941^2 + 7650^2 .

It is a cyclic number.

It is not a de Polignac number, because 380401981 - 2⁵ = 380401949 is a prime.

It is a super-2 number, since 2×380401981² = 289411334297448722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (380401081) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190200990 + 190200991.

It is an arithmetic number, because the mean of its divisors is an integer number (190200991).

Almost surely, 2^380401981 is an apocalyptic number.

It is an amenable number.

380401981 is a deficient number, since it is larger than the sum of its proper divisors (1).

380401981 is an equidigital number, since it uses as much as digits as its factorization.

380401981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6912, while the sum is 34.

The square root of 380401981 is about 19503.8965594058. The cubic root of 380401981 is about 724.5709588350.

The spelling of 380401981 in words is "three hundred eighty million, four hundred one thousand, nine hundred eighty-one".