20721162 has 32 divisors (see below), whose sum is σ = 51669504. Its totient is φ = 5382000.

The previous prime is 20721161. The next prime is 20721163. The reversal of 20721162 is 26112702.

It is an interprime number because it is at equal distance from previous prime (20721161) and next prime (20721163).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is not an unprimeable number, because it can be changed into a prime (20721161) 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 15 ways as a sum of consecutive naturals, for example, 21964 + ... + 22887.

It is an arithmetic number, because the mean of its divisors is an integer number (1614672).

Almost surely, 2^20721162 is an apocalyptic number.

20721162 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20721162 is an abundant number, since it is smaller than the sum of its proper divisors (30948342).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20721162 is a wasteful number, since it uses less digits than its factorization.

20721162 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44874.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 20721162 is about 4552.0503072791. The cubic root of 20721162 is about 274.6658729855.

Adding to 20721162 its reverse (26112702), we get a palindrome (46833864).

The spelling of 20721162 in words is "twenty million, seven hundred twenty-one thousand, one hundred sixty-two".