3891851 has 2 divisors, whose sum is σ = 3891852. Its totient is φ = 3891850.

The previous prime is 3891847. The next prime is 3891857. The reversal of 3891851 is 1581983.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 3891851 - 2² = 3891847 is a prime.

It is an Ulam number.

It is not a weakly prime, because it can be changed into another prime (3891857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1945925 + 1945926.

It is an arithmetic number, because the mean of its divisors is an integer number (1945926).

Almost surely, 2^3891851 is an apocalyptic number.

3891851 is a deficient number, since it is larger than the sum of its proper divisors (1).

3891851 is an equidigital number, since it uses as much as digits as its factorization.

3891851 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8640, while the sum is 35.

The square root of 3891851 is about 1972.7774836509. Note that the first 3 decimals coincide. The cubic root of 3891851 is about 157.2963825455.

The spelling of 3891851 in words is "three million, eight hundred ninety-one thousand, eight hundred fifty-one".