20029581 has 48 divisors (see below), whose sum is σ = 34594560. Its totient is φ = 11007360.

The previous prime is 20029579. The next prime is 20029609. The reversal of 20029581 is 18592002.

It is not a de Polignac number, because 20029581 - 2¹ = 20029579 is a prime.

It is a super-2 number, since 2×20029581² = 802368230071122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20029501) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 101575 + ... + 101771.

It is an arithmetic number, because the mean of its divisors is an integer number (720720).

Almost surely, 2^20029581 is an apocalyptic number.

It is an amenable number.

20029581 is a deficient number, since it is larger than the sum of its proper divisors (14564979).

20029581 is a wasteful number, since it uses less digits than its factorization.

20029581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 306 (or 303 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 20029581 is about 4475.4419893459. The cubic root of 20029581 is about 271.5755210481.

The spelling of 20029581 in words is "twenty million, twenty-nine thousand, five hundred eighty-one".