21434129 has 4 divisors (see below), whose sum is σ = 21465840. Its totient is φ = 21402420.

The previous prime is 21434123. The next prime is 21434131. The reversal of 21434129 is 92143412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21434129 - 2⁸ = 21433873 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21434098 and 21434107.

It is not an unprimeable number, because it can be changed into a prime (21434123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14819 + ... + 16200.

It is an arithmetic number, because the mean of its divisors is an integer number (5366460).

Almost surely, 2^21434129 is an apocalyptic number.

It is an amenable number.

21434129 is a deficient number, since it is larger than the sum of its proper divisors (31711).

21434129 is an equidigital number, since it uses as much as digits as its factorization.

21434129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31710.

The product of its digits is 1728, while the sum is 26.

The square root of 21434129 is about 4629.7007462686. The cubic root of 21434129 is about 277.7806224361.

It can be divided in two parts, 214 and 34129, that added together give a palindrome (34343).

The spelling of 21434129 in words is "twenty-one million, four hundred thirty-four thousand, one hundred twenty-nine".