2120857 has 4 divisors (see below), whose sum is σ = 2194020. Its totient is φ = 2047696.

The previous prime is 2120851. The next prime is 2120863. The reversal of 2120857 is 7580212.

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

It is an interprime number because it is at equal distance from previous prime (2120851) and next prime (2120863).

It can be written as a sum of positive squares in 2 ways, for example, as 1382976 + 737881 = 1176^2 + 859^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120857 - 2³ = 2120849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2120851) 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, 36538 + ... + 36595.

It is an arithmetic number, because the mean of its divisors is an integer number (548505).

2^2120857 is an apocalyptic number.

It is an amenable number.

2120857 is a deficient number, since it is larger than the sum of its proper divisors (73163).

2120857 is an equidigital number, since it uses as much as digits as its factorization.

2120857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73162.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 2120857 is about 1456.3162431285. The cubic root of 2120857 is about 128.4804736488.

The spelling of 2120857 in words is "two million, one hundred twenty thousand, eight hundred fifty-seven".