21488617 has 8 divisors (see below), whose sum is σ = 21873600. Its totient is φ = 21106800.

The previous prime is 21488609. The next prime is 21488641. The reversal of 21488617 is 71688412.

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

It is a cyclic number.

It is not a de Polignac number, because 21488617 - 2³ = 21488609 is a prime.

It is a super-3 number, since 3×21488617³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21488317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15867 + ... + 17167.

It is an arithmetic number, because the mean of its divisors is an integer number (2734200).

Almost surely, 2^21488617 is an apocalyptic number.

It is an amenable number.

21488617 is a deficient number, since it is larger than the sum of its proper divisors (384983).

21488617 is a wasteful number, since it uses less digits than its factorization.

21488617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1583.

The product of its digits is 21504, while the sum is 37.

The square root of 21488617 is about 4635.5816247802. The cubic root of 21488617 is about 278.0158065991.

It can be divided in two parts, 214 and 88617, that added together give a triangular number (88831 = T₄₂₁).

The spelling of 21488617 in words is "twenty-one million, four hundred eighty-eight thousand, six hundred seventeen".