381373661 has 2 divisors, whose sum is σ = 381373662. Its totient is φ = 381373660.

The previous prime is 381373627. The next prime is 381373673. The reversal of 381373661 is 166373183.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 345253561 + 36120100 = 18581^2 + 6010^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-381373661 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (381373691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 190686830 + 190686831.

It is an arithmetic number, because the mean of its divisors is an integer number (190686831).

Almost surely, 2^381373661 is an apocalyptic number.

It is an amenable number.

381373661 is a deficient number, since it is larger than the sum of its proper divisors (1).

381373661 is an equidigital number, since it uses as much as digits as its factorization.

381373661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 38.

The square root of 381373661 is about 19528.7905667504. The cubic root of 381373661 is about 725.1873703586.

The spelling of 381373661 in words is "three hundred eighty-one million, three hundred seventy-three thousand, six hundred sixty-one".