20629009 has 4 divisors (see below), whose sum is σ = 20752704. Its totient is φ = 20505316.

The previous prime is 20628983. The next prime is 20629019. The reversal of 20629009 is 90092602.

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 20629009 - 2⁵ = 20628977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20629019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 61597 + ... + 61930.

It is an arithmetic number, because the mean of its divisors is an integer number (5188176).

Almost surely, 2^20629009 is an apocalyptic number.

It is an amenable number.

20629009 is a deficient number, since it is larger than the sum of its proper divisors (123695).

20629009 is a wasteful number, since it uses less digits than its factorization.

20629009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123694.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 20629009 is about 4541.9168860735. The cubic root of 20629009 is about 274.2580950276.

The spelling of 20629009 in words is "twenty million, six hundred twenty-nine thousand, nine".