20820916 has 12 divisors (see below), whose sum is σ = 36777888. Its totient is φ = 10312952.

The previous prime is 20820889. The next prime is 20820929. The reversal of 20820916 is 61902802.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23896 + ... + 24751.

It is an arithmetic number, because the mean of its divisors is an integer number (3064824).

Almost surely, 2^20820916 is an apocalyptic number.

It is an amenable number.

20820916 is a deficient number, since it is larger than the sum of its proper divisors (15956972).

20820916 is a wasteful number, since it uses less digits than its factorization.

20820916 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48758 (or 48756 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 20820916 is about 4562.9941924136. The cubic root of 20820916 is about 275.1059250346.

It can be divided in two parts, 20820 and 916, that added together give a triangular number (21736 = T₂₀₈).

The spelling of 20820916 in words is "twenty million, eight hundred twenty thousand, nine hundred sixteen".