3945551 has 4 divisors (see below), whose sum is σ = 4037352. Its totient is φ = 3853752.

The previous prime is 3945527. The next prime is 3945607. The reversal of 3945551 is 1555493.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1555493 = 349 ⋅4457.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3945551 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 (3941551) 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, 45836 + ... + 45921.

It is an arithmetic number, because the mean of its divisors is an integer number (1009338).

Almost surely, 2^3945551 is an apocalyptic number.

3945551 is a deficient number, since it is larger than the sum of its proper divisors (91801).

3945551 is an equidigital number, since it uses as much as digits as its factorization.

3945551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91800.

The product of its digits is 13500, while the sum is 32.

The square root of 3945551 is about 1986.3411086719. The cubic root of 3945551 is about 158.0165420911.

The spelling of 3945551 in words is "three million, nine hundred forty-five thousand, five hundred fifty-one".