858404857 has 4 divisors (see below), whose sum is σ = 903584080. Its totient is φ = 813225636.

The previous prime is 858404837. The next prime is 858404861. The reversal of 858404857 is 758404858.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 758404858 = 2 ⋅379202429.

It is a cyclic number.

It is not a de Polignac number, because 858404857 - 2¹⁵ = 858372089 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 858404857.

It is not an unprimeable number, because it can be changed into a prime (858404837) 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, 22589583 + ... + 22589620.

It is an arithmetic number, because the mean of its divisors is an integer number (225896020).

Almost surely, 2^858404857 is an apocalyptic number.

It is an amenable number.

858404857 is a deficient number, since it is larger than the sum of its proper divisors (45179223).

858404857 is a wasteful number, since it uses less digits than its factorization.

858404857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45179222.

The product of its (nonzero) digits is 1433600, while the sum is 49.

The square root of 858404857 is about 29298.5470117547. The cubic root of 858404857 is about 950.3802197337.

Subtracting from 858404857 its reverse (758404858), we obtain a palindrome (99999999).

The spelling of 858404857 in words is "eight hundred fifty-eight million, four hundred four thousand, eight hundred fifty-seven".