20749983 has 8 divisors (see below), whose sum is σ = 28255488. Its totient is φ = 13538904.

The previous prime is 20749969. The next prime is 20749987. The reversal of 20749983 is 38994702.

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

It is a de Polignac number, because none of the positive numbers 2^k-20749983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20749987) 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, 73441 + ... + 73722.

It is an arithmetic number, because the mean of its divisors is an integer number (3531936).

Almost surely, 2^20749983 is an apocalyptic number.

20749983 is a deficient number, since it is larger than the sum of its proper divisors (7505505).

20749983 is a wasteful number, since it uses less digits than its factorization.

20749983 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147213.

The product of its (nonzero) digits is 108864, while the sum is 42.

The square root of 20749983 is about 4555.2149235793. The cubic root of 20749983 is about 274.7931579608.

The spelling of 20749983 in words is "twenty million, seven hundred forty-nine thousand, nine hundred eighty-three".