20480391 has 16 divisors (see below), whose sum is σ = 30988800. Its totient is φ = 13362264.

The previous prime is 20480389. The next prime is 20480431. The reversal of 20480391 is 19308402.

It is not a de Polignac number, because 20480391 - 2¹ = 20480389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20480321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6801 + ... + 9338.

It is an arithmetic number, because the mean of its divisors is an integer number (1936800).

Almost surely, 2^20480391 is an apocalyptic number.

20480391 is a deficient number, since it is larger than the sum of its proper divisors (10508409).

20480391 is a wasteful number, since it uses less digits than its factorization.

20480391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16195 (or 16189 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 20480391 is about 4525.5265991926. The cubic root of 20480391 is about 273.5978926046.

Adding to 20480391 its reverse (19308402), we get a palindrome (39788793).

The spelling of 20480391 in words is "twenty million, four hundred eighty thousand, three hundred ninety-one".