20642929 has 8 divisors (see below), whose sum is σ = 21257960. Its totient is φ = 20030976.

The previous prime is 20642903. The next prime is 20642971. The reversal of 20642929 is 92924602.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 6012304 + 14630625 = 2452^2 + 3825^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20642929 - 2¹¹ = 20640881 is a prime.

It is a super-2 number, since 2×20642929² = 852261035398082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20642894 and 20642903.

It is not an unprimeable number, because it can be changed into a prime (20642129) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24487 + ... + 25315.

It is an arithmetic number, because the mean of its divisors is an integer number (2657245).

Almost surely, 2^20642929 is an apocalyptic number.

It is an amenable number.

20642929 is a deficient number, since it is larger than the sum of its proper divisors (615031).

20642929 is an equidigital number, since it uses as much as digits as its factorization.

20642929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1539.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 20642929 is about 4543.4490202928. The cubic root of 20642929 is about 274.3197689276.

The spelling of 20642929 in words is "twenty million, six hundred forty-two thousand, nine hundred twenty-nine".