21486670 has 32 divisors (see below), whose sum is σ = 40030848. Its totient is φ = 8298528.

The previous prime is 21486649. The next prime is 21486671. The reversal of 21486670 is 7668412.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21486671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 45777 + ... + 46243.

It is an arithmetic number, because the mean of its divisors is an integer number (1250964).

Almost surely, 2^21486670 is an apocalyptic number.

21486670 is a deficient number, since it is larger than the sum of its proper divisors (18544178).

21486670 is a wasteful number, since it uses less digits than its factorization.

21486670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 624.

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 21486670 is about 4635.3716140133. The cubic root of 21486670 is about 278.0074097019.

The spelling of 21486670 in words is "twenty-one million, four hundred eighty-six thousand, six hundred seventy".