20451006 has 24 divisors (see below), whose sum is σ = 44394480. Its totient is φ = 6804096.

The previous prime is 20451001. The next prime is 20451007. The reversal of 20451006 is 60015402.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a self number, because there is not a number n which added to its sum of digits gives 20451006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20451001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16111 + ... + 17333.

It is an arithmetic number, because the mean of its divisors is an integer number (1849770).

Almost surely, 2^20451006 is an apocalyptic number.

20451006 is an abundant number, since it is smaller than the sum of its proper divisors (23943474).

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

20451006 is a wasteful number, since it uses less digits than its factorization.

20451006 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2160 (or 2157 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20451006 is about 4522.2788503143. The cubic root of 20451006 is about 273.4669784012.

Adding to 20451006 its reverse (60015402), we get a palindrome (80466408).

The spelling of 20451006 in words is "twenty million, four hundred fifty-one thousand, six".