20621706 has 16 divisors (see below), whose sum is σ = 47135424. Its totient is φ = 5891904.

The previous prime is 20621693. The next prime is 20621759. The reversal of 20621706 is 60712602.

It is a happy number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 245455 + ... + 245538.

It is an arithmetic number, because the mean of its divisors is an integer number (2945964).

Almost surely, 2^20621706 is an apocalyptic number.

20621706 is an abundant number, since it is smaller than the sum of its proper divisors (26513718).

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

20621706 is a wasteful number, since it uses less digits than its factorization.

20621706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491005.

The product of its (nonzero) digits is 1008, while the sum is 24.

The square root of 20621706 is about 4541.1128592009. The cubic root of 20621706 is about 274.2257272865.

It can be divided in two parts, 206 and 21706, that added together give a palindrome (21912).

The spelling of 20621706 in words is "twenty million, six hundred twenty-one thousand, seven hundred six".