402186381 has 4 divisors (see below), whose sum is σ = 536248512. Its totient is φ = 268124252.

The previous prime is 402186373. The next prime is 402186397. The reversal of 402186381 is 183681204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 402186381 - 2³ = 402186373 is a prime.

It is a super-2 number, since 2×402186381² = 323507770123754322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402186341) 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, 67031061 + ... + 67031066.

It is an arithmetic number, because the mean of its divisors is an integer number (134062128).

Almost surely, 2^402186381 is an apocalyptic number.

It is an amenable number.

402186381 is a deficient number, since it is larger than the sum of its proper divisors (134062131).

402186381 is a wasteful number, since it uses less digits than its factorization.

402186381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134062130.

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 402186381 is about 20054.5850368438. The cubic root of 402186381 is about 738.1463106189.

The spelling of 402186381 in words is "four hundred two million, one hundred eighty-six thousand, three hundred eighty-one".