19900745 has 8 divisors (see below), whose sum is σ = 23910216. Its totient is φ = 15901056.

The previous prime is 19900739. The next prime is 19900747. The reversal of 19900745 is 54700991.

It can be written as a sum of positive squares in 4 ways, for example, as 13454224 + 6446521 = 3668^2 + 2539^2 .

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 19900745 - 2¹⁰ = 19899721 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (19900747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3239 + ... + 7091.

It is an arithmetic number, because the mean of its divisors is an integer number (2988777).

Almost surely, 2^19900745 is an apocalyptic number.

It is an amenable number.

19900745 is a deficient number, since it is larger than the sum of its proper divisors (4009471).

19900745 is a wasteful number, since it uses less digits than its factorization.

19900745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4891.

The product of its (nonzero) digits is 11340, while the sum is 35.

The square root of 19900745 is about 4461.0251064077. The cubic root of 19900745 is about 270.9919842584.

The spelling of 19900745 in words is "nineteen million, nine hundred thousand, seven hundred forty-five".