20923680 has 48 divisors (see below), whose sum is σ = 65911104. Its totient is φ = 5579520.

The previous prime is 20923657. The next prime is 20923687. The reversal of 20923680 is 8632902.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a plaindrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (20923687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21316 + ... + 22275.

It is an arithmetic number, because the mean of its divisors is an integer number (1373148).

Almost surely, 2^20923680 is an apocalyptic number.

20923680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20923680 is an abundant number, since it is smaller than the sum of its proper divisors (44987424).

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

20923680 is a wasteful number, since it uses less digits than its factorization.

20923680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43609 (or 43601 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 20923680 is about 4574.2409206337. The cubic root of 20923680 is about 275.5577879728.

The spelling of 20923680 in words is "twenty million, nine hundred twenty-three thousand, six hundred eighty".