20421310 has 32 divisors (see below), whose sum is σ = 45243072. Its totient is φ = 6462720.

The previous prime is 20421287. The next prime is 20421329. The reversal of 20421310 is 1312402.

It is a super-2 number, since 2×20421310² = 834059804232200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a plaindrome in base 16.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10311 + ... + 12130.

It is an arithmetic number, because the mean of its divisors is an integer number (1413846).

Almost surely, 2^20421310 is an apocalyptic number.

20421310 is an abundant number, since it is smaller than the sum of its proper divisors (24821762).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20421310 is a wasteful number, since it uses less digits than its factorization.

20421310 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22468.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 20421310 is about 4518.9943571551. The cubic root of 20421310 is about 273.3345511876.

Adding to 20421310 its reverse (1312402), we get a palindrome (21733712).

The spelling of 20421310 in words is "twenty million, four hundred twenty-one thousand, three hundred ten".