20730749 has 8 divisors (see below), whose sum is σ = 22428672. Its totient is φ = 19047600.

The previous prime is 20730739. The next prime is 20730757. The reversal of 20730749 is 94703702.

It is a happy number.

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

It is not a de Polignac number, because 20730749 - 2⁴ = 20730733 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20730719) 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, 677 + ... + 6474.

It is an arithmetic number, because the mean of its divisors is an integer number (2803584).

Almost surely, 2^20730749 is an apocalyptic number.

It is an amenable number.

20730749 is a deficient number, since it is larger than the sum of its proper divisors (1697923).

20730749 is a wasteful number, since it uses less digits than its factorization.

20730749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7387.

The product of its (nonzero) digits is 10584, while the sum is 32.

The square root of 20730749 is about 4553.1032274702. The cubic root of 20730749 is about 274.7082260757.

The spelling of 20730749 in words is "twenty million, seven hundred thirty thousand, seven hundred forty-nine".