7877861 has 2 divisors, whose sum is σ = 7877862. Its totient is φ = 7877860.

The previous prime is 7877843. The next prime is 7877873. The reversal of 7877861 is 1687787.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7873636 + 4225 = 2806^2 + 65^2 .

It is a cyclic number.

It is not a de Polignac number, because 7877861 - 2⁶ = 7877797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7877561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3938930 + 3938931.

It is an arithmetic number, because the mean of its divisors is an integer number (3938931).

Almost surely, 2^7877861 is an apocalyptic number.

It is an amenable number.

7877861 is a deficient number, since it is larger than the sum of its proper divisors (1).

7877861 is an equidigital number, since it uses as much as digits as its factorization.

7877861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 131712, while the sum is 44.

The square root of 7877861 is about 2806.7527500655. The cubic root of 7877861 is about 198.9769507744.

It can be divided in two parts, 787786 and 1, that added together give a palindrome (787787).

The spelling of 7877861 in words is "seven million, eight hundred seventy-seven thousand, eight hundred sixty-one".