3921557 has 4 divisors (see below), whose sum is σ = 4012800. Its totient is φ = 3830316.

The previous prime is 3921551. The next prime is 3921559. The reversal of 3921557 is 7551293.

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 3921557 - 2⁸ = 3921301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3921551) 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, 45557 + ... + 45642.

It is an arithmetic number, because the mean of its divisors is an integer number (1003200).

Almost surely, 2^3921557 is an apocalyptic number.

It is an amenable number.

3921557 is a deficient number, since it is larger than the sum of its proper divisors (91243).

3921557 is an equidigital number, since it uses as much as digits as its factorization.

3921557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91242.

The product of its digits is 9450, while the sum is 32.

The square root of 3921557 is about 1980.2921501637. The cubic root of 3921557 is about 157.6955763077.

The spelling of 3921557 in words is "three million, nine hundred twenty-one thousand, five hundred fifty-seven".