21265629 has 24 divisors (see below), whose sum is σ = 35622720. Its totient is φ = 11045760.

The previous prime is 21265619. The next prime is 21265631. The reversal of 21265629 is 92656212.

It is not a de Polignac number, because 21265629 - 2⁸ = 21265373 is a prime.

It is a super-3 number, since 3×21265629³ (a number of 23 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 21265629.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21265619) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1644 + ... + 6725.

It is an arithmetic number, because the mean of its divisors is an integer number (1484280).

Almost surely, 2^21265629 is an apocalyptic number.

It is an amenable number.

21265629 is a deficient number, since it is larger than the sum of its proper divisors (14357091).

21265629 is a wasteful number, since it uses less digits than its factorization.

21265629 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8401 (or 8390 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 21265629 is about 4611.4671201257. The cubic root of 21265629 is about 277.0508015449.

The spelling of 21265629 in words is "twenty-one million, two hundred sixty-five thousand, six hundred twenty-nine".