21429145 has 8 divisors (see below), whose sum is σ = 26040960. Its totient is φ = 16926000.

The previous prime is 21429137. The next prime is 21429167. The reversal of 21429145 is 54192412.

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

It is not a de Polignac number, because 21429145 - 2³ = 21429137 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26731 + ... + 27520.

It is an arithmetic number, because the mean of its divisors is an integer number (3255120).

Almost surely, 2^21429145 is an apocalyptic number.

It is an amenable number.

21429145 is a deficient number, since it is larger than the sum of its proper divisors (4611815).

21429145 is an equidigital number, since it uses as much as digits as its factorization.

21429145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54335.

The product of its digits is 2880, while the sum is 28.

The square root of 21429145 is about 4629.1624512432. The cubic root of 21429145 is about 277.7590903280.

The spelling of 21429145 in words is "twenty-one million, four hundred twenty-nine thousand, one hundred forty-five".