20437939 has 4 divisors (see below), whose sum is σ = 21513640. Its totient is φ = 19362240.

The previous prime is 20437933. The next prime is 20437951. The reversal of 20437939 is 93973402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20437939 - 2⁷ = 20437811 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20437898 and 20437907.

It is not an unprimeable number, because it can be changed into a prime (20437933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537822 + ... + 537859.

It is an arithmetic number, because the mean of its divisors is an integer number (5378410).

Almost surely, 2^20437939 is an apocalyptic number.

20437939 is a deficient number, since it is larger than the sum of its proper divisors (1075701).

20437939 is a wasteful number, since it uses less digits than its factorization.

20437939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075700.

The product of its (nonzero) digits is 40824, while the sum is 37.

The square root of 20437939 is about 4520.8338832565. The cubic root of 20437939 is about 273.4087228426.

The spelling of 20437939 in words is "twenty million, four hundred thirty-seven thousand, nine hundred thirty-nine".