21155662 has 16 divisors (see below), whose sum is σ = 34964784. Its totient is φ = 9520000.

The previous prime is 21155627. The next prime is 21155663. The reversal of 21155662 is 26655112.

It is a self number, because there is not a number n which added to its sum of digits gives 21155662.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21155663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2539 + ... + 6982.

It is an arithmetic number, because the mean of its divisors is an integer number (2185299).

Almost surely, 2^21155662 is an apocalyptic number.

21155662 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21155662 is a deficient number, since it is larger than the sum of its proper divisors (13809122).

21155662 is a wasteful number, since it uses less digits than its factorization.

21155662 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9635.

The product of its digits is 3600, while the sum is 28.

The square root of 21155662 is about 4599.5284540918. The cubic root of 21155662 is about 276.5724222152.

It can be divided in two parts, 2115 and 5662, that added together give a palindrome (7777).

The spelling of 21155662 in words is "twenty-one million, one hundred fifty-five thousand, six hundred sixty-two".