3977781 has 8 divisors (see below), whose sum is σ = 5534400. Its totient is φ = 2536512.

The previous prime is 3977777. The next prime is 3977791. The reversal of 3977781 is 1877793.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 3977781 - 2² = 3977777 is a prime.

It is a super-2 number, since 2×3977781² = 31645483367922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3977731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28756 + ... + 28893.

It is an arithmetic number, because the mean of its divisors is an integer number (691800).

Almost surely, 2^3977781 is an apocalyptic number.

It is an amenable number.

3977781 is a deficient number, since it is larger than the sum of its proper divisors (1556619).

3977781 is a wasteful number, since it uses less digits than its factorization.

3977781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57675.

The product of its digits is 74088, while the sum is 42.

The square root of 3977781 is about 1994.4375146893. The cubic root of 3977781 is about 158.4456387597.

The spelling of 3977781 in words is "three million, nine hundred seventy-seven thousand, seven hundred eighty-one".