857445887 has 4 divisors (see below), whose sum is σ = 857693616. Its totient is φ = 857198160.

The previous prime is 857445877. The next prime is 857445893. The reversal of 857445887 is 788544758.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 788544758 = 2 ⋅394272379.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-857445887 is a prime.

It is a super-4 number, since 4×857445887⁴ (a number of 37 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (857445817) 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, 118598 + ... + 125619.

It is an arithmetic number, because the mean of its divisors is an integer number (214423404).

Almost surely, 2^857445887 is an apocalyptic number.

857445887 is a deficient number, since it is larger than the sum of its proper divisors (247729).

857445887 is a wasteful number, since it uses less digits than its factorization.

857445887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 247728.

The product of its digits is 10035200, while the sum is 56.

The square root of 857445887 is about 29282.1769511763. The cubic root of 857445887 is about 950.0261809959.

The spelling of 857445887 in words is "eight hundred fifty-seven million, four hundred forty-five thousand, eight hundred eighty-seven".