2386781 has 2 divisors, whose sum is σ = 2386782. Its totient is φ = 2386780.

The previous prime is 2386777. The next prime is 2386789. The reversal of 2386781 is 1876832.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2374681 + 12100 = 1541^2 + 110^2 .

It is a cyclic number.

It is not a de Polignac number, because 2386781 - 2² = 2386777 is a prime.

It is a super-2 number, since 2×2386781² = 11393447083922, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2386789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1193390 + 1193391.

It is an arithmetic number, because the mean of its divisors is an integer number (1193391).

2^2386781 is an apocalyptic number.

It is an amenable number.

2386781 is a deficient number, since it is larger than the sum of its proper divisors (1).

2386781 is an equidigital number, since it uses as much as digits as its factorization.

2386781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 16128, while the sum is 35.

The square root of 2386781 is about 1544.9210335807. The cubic root of 2386781 is about 133.6403252661.

The spelling of 2386781 in words is "two million, three hundred eighty-six thousand, seven hundred eighty-one".