20570691 has 4 divisors (see below), whose sum is σ = 27427592. Its totient is φ = 13713792.

The previous prime is 20570689. The next prime is 20570707. The reversal of 20570691 is 19607502.

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

It is not a de Polignac number, because 20570691 - 2¹ = 20570689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20570681) 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, 3428446 + ... + 3428451.

It is an arithmetic number, because the mean of its divisors is an integer number (6856898).

Almost surely, 2^20570691 is an apocalyptic number.

20570691 is a deficient number, since it is larger than the sum of its proper divisors (6856901).

20570691 is an equidigital number, since it uses as much as digits as its factorization.

20570691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6856900.

The product of its (nonzero) digits is 3780, while the sum is 30.

The square root of 20570691 is about 4535.4923657746. The cubic root of 20570691 is about 273.9994094860. Note that the first 3 decimals are identical.

The spelling of 20570691 in words is "twenty million, five hundred seventy thousand, six hundred ninety-one".