20749874 has 4 divisors (see below), whose sum is σ = 31124814. Its totient is φ = 10374936.

The previous prime is 20749837. The next prime is 20749879. The reversal of 20749874 is 47894702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 47894702 = 2 ⋅23947351.

It can be written as a sum of positive squares in only one way, i.e., 20748025 + 1849 = 4555^2 + 43^2 .

It is not an unprimeable number, because it can be changed into a prime (20749879) 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 as a sum of consecutive naturals, namely, 5187467 + ... + 5187470.

Almost surely, 2^20749874 is an apocalyptic number.

20749874 is a deficient number, since it is larger than the sum of its proper divisors (10374940).

20749874 is a wasteful number, since it uses less digits than its factorization.

20749874 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10374939.

The product of its (nonzero) digits is 112896, while the sum is 41.

The square root of 20749874 is about 4555.2029592544. The cubic root of 20749874 is about 274.7926767956.

The spelling of 20749874 in words is "twenty million, seven hundred forty-nine thousand, eight hundred seventy-four".