21516196 has 24 divisors (see below), whose sum is σ = 40836600. Its totient is φ = 9860352.

The previous prime is 21516193. The next prime is 21516197. The reversal of 21516196 is 69161512.

It can be written as a sum of positive squares in 4 ways, for example, as 940900 + 20575296 = 970^2 + 4536^2 .

It is not an unprimeable number, because it can be changed into a prime (21516191) 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 7 ways as a sum of consecutive naturals, for example, 6360 + ... + 9136.

It is an arithmetic number, because the mean of its divisors is an integer number (1701525).

Almost surely, 2^21516196 is an apocalyptic number.

21516196 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21516196 is a deficient number, since it is larger than the sum of its proper divisors (19320404).

21516196 is a wasteful number, since it uses less digits than its factorization.

21516196 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2943 (or 2941 counting only the distinct ones).

The product of its digits is 3240, while the sum is 31.

The square root of 21516196 is about 4638.5553785635. Note that the first 3 decimals coincide. The cubic root of 21516196 is about 278.1346931100.

It can be divided in two parts, 21516 and 196, that added together give a palindrome (21712).

The spelling of 21516196 in words is "twenty-one million, five hundred sixteen thousand, one hundred ninety-six".