20399029 has 4 divisors (see below), whose sum is σ = 23313184. Its totient is φ = 17484876.

The previous prime is 20399009. The next prime is 20399033. The reversal of 20399029 is 92099302.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20399029 - 2¹⁷ = 20267957 is a prime.

It is a super-2 number, since 2×20399029² = 832240768285682, 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 = 20398985 and 20399003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20399009) 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, 1457067 + ... + 1457080.

It is an arithmetic number, because the mean of its divisors is an integer number (5828296).

Almost surely, 2^20399029 is an apocalyptic number.

It is an amenable number.

20399029 is a deficient number, since it is larger than the sum of its proper divisors (2914155).

20399029 is an equidigital number, since it uses as much as digits as its factorization.

20399029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914154.

The product of its (nonzero) digits is 8748, while the sum is 34.

The square root of 20399029 is about 4516.5284234686. The cubic root of 20399029 is about 273.2351063201.

The spelling of 20399029 in words is "twenty million, three hundred ninety-nine thousand, twenty-nine".