21346870 has 32 divisors (see below), whose sum is σ = 39442176. Its totient is φ = 8316000.

The previous prime is 21346867. The next prime is 21346873. The reversal of 21346870 is 7864312.

It is an interprime number because it is at equal distance from previous prime (21346867) and next prime (21346873).

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21346873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 101065 + ... + 101275.

It is an arithmetic number, because the mean of its divisors is an integer number (1232568).

Almost surely, 2^21346870 is an apocalyptic number.

21346870 is a deficient number, since it is larger than the sum of its proper divisors (18095306).

21346870 is a wasteful number, since it uses less digits than its factorization.

21346870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 21346870 is about 4620.2673082842. The cubic root of 21346870 is about 277.4031585900.

The spelling of 21346870 in words is "twenty-one million, three hundred forty-six thousand, eight hundred seventy".