3857981987 has 2 divisors, whose sum is σ = 3857981988. Its totient is φ = 3857981986.

The previous prime is 3857981951. The next prime is 3857981993. The reversal of 3857981987 is 7891897583.

It is a happy number.

3857981987 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 3857981987 - 2⁶ = 3857981923 is a prime.

It is not a weakly prime, because it can be changed into another prime (3857981917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1928990993 + 1928990994.

It is an arithmetic number, because the mean of its divisors is an integer number (1928990994).

Almost surely, 2^3857981987 is an apocalyptic number.

3857981987 is a deficient number, since it is larger than the sum of its proper divisors (1).

3857981987 is an equidigital number, since it uses as much as digits as its factorization.

3857981987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30481920, while the sum is 65.

The square root of 3857981987 is about 62112.6556105920. The cubic root of 3857981987 is about 1568.3875946141.

The spelling of 3857981987 in words is "three billion, eight hundred fifty-seven million, nine hundred eighty-one thousand, nine hundred eighty-seven".