21752899 has 8 divisors (see below), whose sum is σ = 24954368. Its totient is φ = 18574920.

The previous prime is 21752893. The next prime is 21752921. The reversal of 21752899 is 99825712.

21752899 = 1240² + 1241² + ... + 1253².

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

It is not a de Polignac number, because 21752899 - 2¹¹ = 21750851 is a prime.

It is a super-2 number, since 2×21752899² = 946377229808402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21752893) 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, 3837 + ... + 7630.

It is an arithmetic number, because the mean of its divisors is an integer number (3119296).

Almost surely, 2^21752899 is an apocalyptic number.

21752899 is a deficient number, since it is larger than the sum of its proper divisors (3201469).

21752899 is a wasteful number, since it uses less digits than its factorization.

21752899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11745.

The product of its digits is 90720, while the sum is 43.

The square root of 21752899 is about 4664.0003216123. Note that the first 3 decimals coincide. The cubic root of 21752899 is about 279.1509099099.

The spelling of 21752899 in words is "twenty-one million, seven hundred fifty-two thousand, eight hundred ninety-nine".