21415672 has 8 divisors (see below), whose sum is σ = 40154400. Its totient is φ = 10707832.

The previous prime is 21415661. The next prime is 21415721. The reversal of 21415672 is 27651412.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×21415672³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21415672.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 1338472 + ... + 1338487.

It is an arithmetic number, because the mean of its divisors is an integer number (5019300).

Almost surely, 2^21415672 is an apocalyptic number.

It is an amenable number.

21415672 is a deficient number, since it is larger than the sum of its proper divisors (18738728).

21415672 is a wasteful number, since it uses less digits than its factorization.

21415672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2676965 (or 2676961 counting only the distinct ones).

The product of its digits is 3360, while the sum is 28.

The square root of 21415672 is about 4627.7069915888. The cubic root of 21415672 is about 277.7008669321.

The spelling of 21415672 in words is "twenty-one million, four hundred fifteen thousand, six hundred seventy-two".