21748953 has 8 divisors (see below), whose sum is σ = 29034208. Its totient is φ = 14481504.

The previous prime is 21748943. The next prime is 21748973. The reversal of 21748953 is 35984712.

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

It is not a de Polignac number, because 21748953 - 2⁶ = 21748889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21748943) 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, 1276 + ... + 6717.

It is an arithmetic number, because the mean of its divisors is an integer number (3629276).

Almost surely, 2^21748953 is an apocalyptic number.

It is an amenable number.

21748953 is a deficient number, since it is larger than the sum of its proper divisors (7285255).

21748953 is an equidigital number, since it uses as much as digits as its factorization.

21748953 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8903.

The product of its digits is 60480, while the sum is 39.

The square root of 21748953 is about 4663.5772750111. The cubic root of 21748953 is about 279.1340294610.

The spelling of 21748953 in words is "twenty-one million, seven hundred forty-eight thousand, nine hundred fifty-three".