20289331 has 4 divisors (see below), whose sum is σ = 20410992. Its totient is φ = 20167672.

The previous prime is 20289319. The next prime is 20289337. The reversal of 20289331 is 13398202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13398202 = 2 ⋅6699101.

It is a cyclic number.

It is not a de Polignac number, because 20289331 - 2¹⁹ = 19765043 is a prime.

It is a super-2 number, since 2×20289331² = 823313904855122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20289331.

It is not an unprimeable number, because it can be changed into a prime (20289337) 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, 60580 + ... + 60913.

It is an arithmetic number, because the mean of its divisors is an integer number (5102748).

Almost surely, 2^20289331 is an apocalyptic number.

20289331 is a deficient number, since it is larger than the sum of its proper divisors (121661).

20289331 is a wasteful number, since it uses less digits than its factorization.

20289331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121660.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 20289331 is about 4504.3679911837. The cubic root of 20289331 is about 272.7444418854.

The spelling of 20289331 in words is "twenty million, two hundred eighty-nine thousand, three hundred thirty-one".