20720434 has 12 divisors (see below), whose sum is σ = 36155214. Its totient is φ = 8880144.

The previous prime is 20720429. The next prime is 20720437. The reversal of 20720434 is 43402702.

It can be written as a sum of positive squares in only one way, i.e., 19386409 + 1334025 = 4403^2 + 1155^2 .

It is not an unprimeable number, because it can be changed into a prime (20720437) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 105619 + ... + 105814.

Almost surely, 2^20720434 is an apocalyptic number.

20720434 is a deficient number, since it is larger than the sum of its proper divisors (15434780).

20720434 is a wasteful number, since it uses less digits than its factorization.

20720434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 211449 (or 211442 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 22.

The square root of 20720434 is about 4551.9703426099. The cubic root of 20720434 is about 274.6626563207.

The spelling of 20720434 in words is "twenty million, seven hundred twenty thousand, four hundred thirty-four".