21434629 has 4 divisors (see below), whose sum is σ = 21528460. Its totient is φ = 21340800.

The previous prime is 21434591. The next prime is 21434639. The reversal of 21434629 is 92643412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 20493729 + 940900 = 4527^2 + 970^2 .

It is a cyclic number.

It is not a de Polignac number, because 21434629 - 2⁹ = 21434117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21434629.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21434639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46572 + ... + 47029.

It is an arithmetic number, because the mean of its divisors is an integer number (5382115).

Almost surely, 2^21434629 is an apocalyptic number.

It is an amenable number.

21434629 is a deficient number, since it is larger than the sum of its proper divisors (93831).

21434629 is an equidigital number, since it uses as much as digits as its factorization.

21434629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93830.

The product of its digits is 10368, while the sum is 31.

The square root of 21434629 is about 4629.7547451242. The cubic root of 21434629 is about 277.7827823750.

It can be divided in two parts, 214 and 34629, that added together give a palindrome (34843).

The spelling of 21434629 in words is "twenty-one million, four hundred thirty-four thousand, six hundred twenty-nine".