21173086 has 8 divisors (see below), whose sum is σ = 34646904. Its totient is φ = 9624120.

The previous prime is 21173081. The next prime is 21173099. The reversal of 21173086 is 68037112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21173081) 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, 481185 + ... + 481228.

It is an arithmetic number, because the mean of its divisors is an integer number (4330863).

Almost surely, 2^21173086 is an apocalyptic number.

21173086 is a deficient number, since it is larger than the sum of its proper divisors (13473818).

21173086 is a wasteful number, since it uses less digits than its factorization.

21173086 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 962426.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 21173086 is about 4601.4221714596. The cubic root of 21173086 is about 276.6483305859.

The spelling of 21173086 in words is "twenty-one million, one hundred seventy-three thousand, eighty-six".