20983577 has 4 divisors (see below), whose sum is σ = 20993460. Its totient is φ = 20973696.

The previous prime is 20983561. The next prime is 20983583. The reversal of 20983577 is 77538902.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 10896601 + 10086976 = 3301^2 + 3176^2 .

It is a cyclic number.

It is not a de Polignac number, because 20983577 - 2⁴ = 20983561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20983507) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 308 + ... + 6485.

It is an arithmetic number, because the mean of its divisors is an integer number (5248365).

Almost surely, 2^20983577 is an apocalyptic number.

It is an amenable number.

20983577 is a deficient number, since it is larger than the sum of its proper divisors (9883).

20983577 is an equidigital number, since it uses as much as digits as its factorization.

20983577 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9882.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 20983577 is about 4580.7834482761. The cubic root of 20983577 is about 275.8204785455.

The spelling of 20983577 in words is "twenty million, nine hundred eighty-three thousand, five hundred seventy-seven".