21742010 has 16 divisors (see below), whose sum is σ = 39267072. Its totient is φ = 8667600.

The previous prime is 21742009. The next prime is 21742027. The reversal of 21742010 is 1024712.

It is a super-3 number, since 3×21742010³ (a number of 23 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21742010.

It is an unprimeable number.

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, 386 + ... + 6605.

It is an arithmetic number, because the mean of its divisors is an integer number (2454192).

Almost surely, 2^21742010 is an apocalyptic number.

21742010 is a deficient number, since it is larger than the sum of its proper divisors (17525062).

21742010 is a wasteful number, since it uses less digits than its factorization.

21742010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7309.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 21742010 is about 4662.8328299436. The cubic root of 21742010 is about 279.1043232979.

Adding to 21742010 its reverse (1024712), we get a palindrome (22766722).

The spelling of 21742010 in words is "twenty-one million, seven hundred forty-two thousand, ten".