20284391 has 8 divisors (see below), whose sum is σ = 20736768. Its totient is φ = 19836000.

The previous prime is 20284379. The next prime is 20284403. The reversal of 20284391 is 19348202.

It is an interprime number because it is at equal distance from previous prime (20284379) and next prime (20284403).

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20284391 is a prime.

It is a super-2 number, since 2×20284391² = 822913036481762, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20284301) 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, 10781 + ... + 12521.

It is an arithmetic number, because the mean of its divisors is an integer number (2592096).

Almost surely, 2^20284391 is an apocalyptic number.

20284391 is a deficient number, since it is larger than the sum of its proper divisors (452377).

20284391 is a wasteful number, since it uses less digits than its factorization.

20284391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1993.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 20284391 is about 4503.8196011830. The cubic root of 20284391 is about 272.7223043573.

The spelling of 20284391 in words is "twenty million, two hundred eighty-four thousand, three hundred ninety-one".