857155213 has 4 divisors (see below), whose sum is σ = 857746588. Its totient is φ = 856563840.

The previous prime is 857155207. The next prime is 857155219. The reversal of 857155213 is 312551758.

It is a happy number.

857155213 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312551758 = 2 ⋅156275879.

It is an interprime number because it is at equal distance from previous prime (857155207) and next prime (857155219).

It can be written as a sum of positive squares in 2 ways, for example, as 814931209 + 42224004 = 28547^2 + 6498^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857155213 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857155219) 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, 293508 + ... + 296413.

It is an arithmetic number, because the mean of its divisors is an integer number (214436647).

Almost surely, 2^857155213 is an apocalyptic number.

It is an amenable number.

857155213 is a deficient number, since it is larger than the sum of its proper divisors (591375).

857155213 is a wasteful number, since it uses less digits than its factorization.

857155213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 591374.

The product of its digits is 42000, while the sum is 37.

The square root of 857155213 is about 29277.2132041286. The cubic root of 857155213 is about 949.9188159618.

The spelling of 857155213 in words is "eight hundred fifty-seven million, one hundred fifty-five thousand, two hundred thirteen".