20729995 has 32 divisors (see below), whose sum is σ = 29675520. Its totient is φ = 13703040.

The previous prime is 20729993. The next prime is 20730011. The reversal of 20729995 is 59992702.

It is not a de Polignac number, because 20729995 - 2¹ = 20729993 is a prime.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (20729993) 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 31 ways as a sum of consecutive naturals, for example, 56302 + ... + 56668.

It is an arithmetic number, because the mean of its divisors is an integer number (927360).

Almost surely, 2^20729995 is an apocalyptic number.

20729995 is a deficient number, since it is larger than the sum of its proper divisors (8945525).

20729995 is a wasteful number, since it uses less digits than its factorization.

20729995 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475.

The product of its (nonzero) digits is 102060, while the sum is 43.

The square root of 20729995 is about 4553.0204260469. The cubic root of 20729995 is about 274.7048955558.

The spelling of 20729995 in words is "twenty million, seven hundred twenty-nine thousand, nine hundred ninety-five".