2991557 has 4 divisors (see below), whose sum is σ = 3025260. Its totient is φ = 2957856.

The previous prime is 2991551. The next prime is 2991559. The reversal of 2991557 is 7551992.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 638401 + 2353156 = 799^2 + 1534^2 .

It is a cyclic number.

It is not a de Polignac number, because 2991557 - 2¹⁴ = 2975173 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2991557.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2991551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16718 + ... + 16895.

It is an arithmetic number, because the mean of its divisors is an integer number (756315).

2^2991557 is an apocalyptic number.

It is an amenable number.

2991557 is a deficient number, since it is larger than the sum of its proper divisors (33703).

2991557 is an equidigital number, since it uses as much as digits as its factorization.

2991557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33702.

The product of its digits is 28350, while the sum is 38.

The square root of 2991557 is about 1729.6118061577. The cubic root of 2991557 is about 144.0895308717.

The spelling of 2991557 in words is "two million, nine hundred ninety-one thousand, five hundred fifty-seven".