20451983 has 8 divisors (see below), whose sum is σ = 20746176. Its totient is φ = 20160000.

The previous prime is 20451979. The next prime is 20452007. The reversal of 20451983 is 38915402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20451983 - 2² = 20451979 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20451973) 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, 26858 + ... + 27608.

It is an arithmetic number, because the mean of its divisors is an integer number (2593272).

Almost surely, 2^20451983 is an apocalyptic number.

20451983 is a deficient number, since it is larger than the sum of its proper divisors (294193).

20451983 is a wasteful number, since it uses less digits than its factorization.

20451983 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 20451983 is about 4522.3868697846. The cubic root of 20451983 is about 273.4713330849.

The spelling of 20451983 in words is "twenty million, four hundred fifty-one thousand, nine hundred eighty-three".