20693856 has 48 divisors (see below), whose sum is σ = 54707184. Its totient is φ = 6849024.

The previous prime is 20693843. The next prime is 20693857. The reversal of 20693856 is 65839602.

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

It is a super-2 number, since 2×20693856² = 856471352297472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20693857) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14386 + ... + 15758.

It is an arithmetic number, because the mean of its divisors is an integer number (1139733).

Almost surely, 2^20693856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20693856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27353592).

20693856 is an abundant number, since it is smaller than the sum of its proper divisors (34013328).

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

20693856 is a wasteful number, since it uses less digits than its factorization.

20693856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1543 (or 1535 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 39.

The square root of 20693856 is about 4549.0500107165. The cubic root of 20693856 is about 274.5451699218.

The spelling of 20693856 in words is "twenty million, six hundred ninety-three thousand, eight hundred fifty-six".