20405434 has 16 divisors (see below), whose sum is σ = 35329536. Its totient is φ = 8658000.

The previous prime is 20405387. The next prime is 20405443. The reversal of 20405434 is 43450402.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5802 + ... + 8629.

It is an arithmetic number, because the mean of its divisors is an integer number (2208096).

Almost surely, 2^20405434 is an apocalyptic number.

20405434 is a deficient number, since it is larger than the sum of its proper divisors (14924102).

20405434 is a wasteful number, since it uses less digits than its factorization.

20405434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14541.

The product of its (nonzero) digits is 1920, while the sum is 22.

The square root of 20405434 is about 4517.2374301115. The cubic root of 20405434 is about 273.2637006178.

Adding to 20405434 its reverse (43450402), we get a palindrome (63855836).

The spelling of 20405434 in words is "twenty million, four hundred five thousand, four hundred thirty-four".