3987405 has 12 divisors (see below), whose sum is σ = 6911580. Its totient is φ = 2126592.

The previous prime is 3987353. The next prime is 3987407. The reversal of 3987405 is 5047893.

It can be written as a sum of positive squares in 2 ways, for example, as 2965284 + 1022121 = 1722^2 + 1011^2 .

It is not a de Polignac number, because 3987405 - 2⁸ = 3987149 is a prime.

3987405 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 3987405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3987407) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 44260 + ... + 44349.

It is an arithmetic number, because the mean of its divisors is an integer number (575965).

Almost surely, 2^3987405 is an apocalyptic number.

It is an amenable number.

3987405 is a deficient number, since it is larger than the sum of its proper divisors (2924175).

3987405 is a wasteful number, since it uses less digits than its factorization.

3987405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 88620 (or 88617 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 3987405 is about 1996.8487674333. The cubic root of 3987405 is about 158.5733190494.

The spelling of 3987405 in words is "three million, nine hundred eighty-seven thousand, four hundred five".