20429665 has 8 divisors (see below), whose sum is σ = 25957800. Its totient is φ = 15382272.

The previous prime is 20429663. The next prime is 20429711. The reversal of 20429665 is 56692402.

It can be written as a sum of positive squares in 4 ways, for example, as 3389281 + 17040384 = 1841^2 + 4128^2 .

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 20429665 - 2¹ = 20429663 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20429665.

It is not an unprimeable number, because it can be changed into a prime (20429663) 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, 120090 + ... + 120259.

It is an arithmetic number, because the mean of its divisors is an integer number (3244725).

Almost surely, 2^20429665 is an apocalyptic number.

It is an amenable number.

20429665 is a deficient number, since it is larger than the sum of its proper divisors (5528135).

20429665 is a wasteful number, since it uses less digits than its factorization.

20429665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240371.

The product of its (nonzero) digits is 25920, while the sum is 34.

The square root of 20429665 is about 4519.9186939590. The cubic root of 20429665 is about 273.3718226915.

The spelling of 20429665 in words is "twenty million, four hundred twenty-nine thousand, six hundred sixty-five".