20757838 has 4 divisors (see below), whose sum is σ = 31136760. Its totient is φ = 10378918.

The previous prime is 20757809. The next prime is 20757853. The reversal of 20757838 is 83875702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83875702 = 2 ⋅41937851.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 20757838.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5189458 + ... + 5189461.

It is an arithmetic number, because the mean of its divisors is an integer number (7784190).

Almost surely, 2^20757838 is an apocalyptic number.

20757838 is a deficient number, since it is larger than the sum of its proper divisors (10378922).

20757838 is a wasteful number, since it uses less digits than its factorization.

20757838 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10378921.

The product of its (nonzero) digits is 94080, while the sum is 40.

The square root of 20757838 is about 4556.0770406129. The cubic root of 20757838 is about 274.8278283176.

The spelling of 20757838 in words is "twenty million, seven hundred fifty-seven thousand, eight hundred thirty-eight".