21472665 has 8 divisors (see below), whose sum is σ = 34356288. Its totient is φ = 11452080.

The previous prime is 21472663. The next prime is 21472667. The reversal of 21472665 is 56627412.

It is an interprime number because it is at equal distance from previous prime (21472663) and next prime (21472667).

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

It is not a de Polignac number, because 21472665 - 2¹ = 21472663 is a prime.

It is a super-2 number, since 2×21472665² = 922150684404450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21472663) 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 7 ways as a sum of consecutive naturals, for example, 715741 + ... + 715770.

It is an arithmetic number, because the mean of its divisors is an integer number (4294536).

Almost surely, 2^21472665 is an apocalyptic number.

It is an amenable number.

21472665 is a deficient number, since it is larger than the sum of its proper divisors (12883623).

21472665 is a wasteful number, since it uses less digits than its factorization.

21472665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1431519.

The product of its digits is 20160, while the sum is 33.

The square root of 21472665 is about 4633.8607014022. The cubic root of 21472665 is about 277.9469948803.

The spelling of 21472665 in words is "twenty-one million, four hundred seventy-two thousand, six hundred sixty-five".