212173857 has 32 divisors (see below), whose sum is σ = 359919360. Its totient is φ = 121011840.

The previous prime is 212173849. The next prime is 212173861. The reversal of 212173857 is 758371212.

It is not a de Polignac number, because 212173857 - 2³ = 212173849 is a prime.

It is not an unprimeable number, because it can be changed into a prime (212173807) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 177253 + ... + 178445.

It is an arithmetic number, because the mean of its divisors is an integer number (11247480).

Almost surely, 2^212173857 is an apocalyptic number.

212173857 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

212173857 is a deficient number, since it is larger than the sum of its proper divisors (147745503).

212173857 is a wasteful number, since it uses less digits than its factorization.

212173857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2150 (or 2144 counting only the distinct ones).

The product of its digits is 23520, while the sum is 36.

The square root of 212173857 is about 14566.1888289285. The cubic root of 212173857 is about 596.4361485160.

The spelling of 212173857 in words is "two hundred twelve million, one hundred seventy-three thousand, eight hundred fifty-seven".