21201429 has 4 divisors (see below), whose sum is σ = 28268576. Its totient is φ = 14134284.

The previous prime is 21201421. The next prime is 21201443. The reversal of 21201429 is 92410212.

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 not a de Polignac number, because 21201429 - 2³ = 21201421 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201421) 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, 3533569 + ... + 3533574.

It is an arithmetic number, because the mean of its divisors is an integer number (7067144).

Almost surely, 2^21201429 is an apocalyptic number.

It is an amenable number.

21201429 is a deficient number, since it is larger than the sum of its proper divisors (7067147).

21201429 is an equidigital number, since it uses as much as digits as its factorization.

21201429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7067146.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 21201429 is about 4604.5009501574. The cubic root of 21201429 is about 276.7717191096.

The spelling of 21201429 in words is "twenty-one million, two hundred one thousand, four hundred twenty-nine".