1958861 has 2 divisors, whose sum is σ = 1958862. Its totient is φ = 1958860.

The previous prime is 1958837. The next prime is 1958867. The reversal of 1958861 is 1688591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1943236 + 15625 = 1394^2 + 125^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1958861 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1958867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 979430 + 979431.

It is an arithmetic number, because the mean of its divisors is an integer number (979431).

2^1958861 is an apocalyptic number.

It is an amenable number.

1958861 is a deficient number, since it is larger than the sum of its proper divisors (1).

1958861 is an equidigital number, since it uses as much as digits as its factorization.

1958861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17280, while the sum is 38.

The square root of 1958861 is about 1399.5931551705. The cubic root of 1958861 is about 125.1222484036.

The spelling of 1958861 in words is "one million, nine hundred fifty-eight thousand, eight hundred sixty-one".