21402059 has 8 divisors (see below), whose sum is σ = 25248768. Its totient is φ = 17752680.

The previous prime is 21402053. The next prime is 21402077. The reversal of 21402059 is 95020412.

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 21402059 - 2²⁰ = 20353483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21402053) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 49097 + ... + 49530.

It is an arithmetic number, because the mean of its divisors is an integer number (3156096).

Almost surely, 2^21402059 is an apocalyptic number.

21402059 is a deficient number, since it is larger than the sum of its proper divisors (3846709).

21402059 is an equidigital number, since it uses as much as digits as its factorization.

21402059 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98665.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 21402059 is about 4626.2359429670. The cubic root of 21402059 is about 277.6420137212.

The spelling of 21402059 in words is "twenty-one million, four hundred two thousand, fifty-nine".