3865421918 has 4 divisors (see below), whose sum is σ = 5798132880. Its totient is φ = 1932710958.

The previous prime is 3865421891. The next prime is 3865421927. The reversal of 3865421918 is 8191245683.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

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, 966355478 + ... + 966355481.

It is an arithmetic number, because the mean of its divisors is an integer number (1449533220).

Almost surely, 2^3865421918 is an apocalyptic number.

3865421918 is a deficient number, since it is larger than the sum of its proper divisors (1932710962).

3865421918 is a wasteful number, since it uses less digits than its factorization.

3865421918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1932710961.

The product of its digits is 414720, while the sum is 47.

The square root of 3865421918 is about 62172.5173850955. The cubic root of 3865421918 is about 1569.3951336775.

The spelling of 3865421918 in words is "three billion, eight hundred sixty-five million, four hundred twenty-one thousand, nine hundred eighteen".