20870427 has 4 divisors (see below), whose sum is σ = 27827240. Its totient is φ = 13913616.

The previous prime is 20870389. The next prime is 20870429. The reversal of 20870427 is 72407802.

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

It is not a de Polignac number, because 20870427 - 2¹⁰ = 20869403 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20870394 and 20870403.

It is not an unprimeable number, because it can be changed into a prime (20870429) 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, 3478402 + ... + 3478407.

It is an arithmetic number, because the mean of its divisors is an integer number (6956810).

Almost surely, 2^20870427 is an apocalyptic number.

20870427 is a deficient number, since it is larger than the sum of its proper divisors (6956813).

20870427 is an equidigital number, since it uses as much as digits as its factorization.

20870427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6956812.

The product of its (nonzero) digits is 6272, while the sum is 30.

The square root of 20870427 is about 4568.4162463593. The cubic root of 20870427 is about 275.3238146992.

The spelling of 20870427 in words is "twenty million, eight hundred seventy thousand, four hundred twenty-seven".