3918729 has 4 divisors (see below), whose sum is σ = 5224976. Its totient is φ = 2612484.

The previous prime is 3918697. The next prime is 3918743. The reversal of 3918729 is 9278193.

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, and also an emirpimes, since its reverse is a distinct semiprime: 9278193 = 3 ⋅3092731.

It is not a de Polignac number, because 3918729 - 2⁵ = 3918697 is a prime.

It is a D-number.

It is a Duffinian number.

3918729 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (3918029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 653119 + ... + 653124.

It is an arithmetic number, because the mean of its divisors is an integer number (1306244).

Almost surely, 2^3918729 is an apocalyptic number.

It is an amenable number.

3918729 is a deficient number, since it is larger than the sum of its proper divisors (1306247).

3918729 is a wasteful number, since it uses less digits than its factorization.

3918729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1306246.

The product of its digits is 27216, while the sum is 39.

The square root of 3918729 is about 1979.5779853292. The cubic root of 3918729 is about 157.6576602169.

The spelling of 3918729 in words is "three million, nine hundred eighteen thousand, seven hundred twenty-nine".