20697443 has 4 divisors (see below), whose sum is σ = 22289568. Its totient is φ = 19105320.

The previous prime is 20697433. The next prime is 20697451. The reversal of 20697443 is 34479602.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34479602 = 2 ⋅17239801.

It is not a de Polignac number, because 20697443 - 2⁶ = 20697379 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20697433) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 796043 + ... + 796068.

It is an arithmetic number, because the mean of its divisors is an integer number (5572392).

Almost surely, 2^20697443 is an apocalyptic number.

20697443 is a deficient number, since it is larger than the sum of its proper divisors (1592125).

20697443 is a wasteful number, since it uses less digits than its factorization.

20697443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1592124.

The product of its (nonzero) digits is 36288, while the sum is 35.

The square root of 20697443 is about 4549.4442517741. Note that the first 3 decimals coincide. The cubic root of 20697443 is about 274.5610319025.

The spelling of 20697443 in words is "twenty million, six hundred ninety-seven thousand, four hundred forty-three".