21292145 has 8 divisors (see below), whose sum is σ = 29200704. Its totient is φ = 14600304.

The previous prime is 21292099. The next prime is 21292147. The reversal of 21292145 is 54129212.

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

It is a cyclic number.

It is not a de Polignac number, because 21292145 - 2⁸ = 21291889 is a prime.

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

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21292147) 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 7 ways as a sum of consecutive naturals, for example, 304139 + ... + 304208.

It is an arithmetic number, because the mean of its divisors is an integer number (3650088).

Almost surely, 2^21292145 is an apocalyptic number.

It is an amenable number.

21292145 is a deficient number, since it is larger than the sum of its proper divisors (7908559).

21292145 is an equidigital number, since it uses as much as digits as its factorization.

21292145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 608359.

The product of its digits is 1440, while the sum is 26.

The square root of 21292145 is about 4614.3412314219. The cubic root of 21292145 is about 277.1659047759.

The spelling of 21292145 in words is "twenty-one million, two hundred ninety-two thousand, one hundred forty-five".