2891858 has 4 divisors (see below), whose sum is σ = 4337790. Its totient is φ = 1445928.

The previous prime is 2891831. The next prime is 2891891. The reversal of 2891858 is 8581982.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8581982 = 2 ⋅4290991.

It can be written as a sum of positive squares in only one way, i.e., 1630729 + 1261129 = 1277^2 + 1123^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 722963 + ... + 722966.

2^2891858 is an apocalyptic number.

2891858 is a deficient number, since it is larger than the sum of its proper divisors (1445932).

2891858 is a wasteful number, since it uses less digits than its factorization.

2891858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1445931.

The product of its digits is 46080, while the sum is 41.

The square root of 2891858 is about 1700.5463827841. The cubic root of 2891858 is about 142.4707316518.

The spelling of 2891858 in words is "two million, eight hundred ninety-one thousand, eight hundred fifty-eight".