21611012 has 24 divisors (see below), whose sum is σ = 40221216. Its totient is φ = 10124928.

The previous prime is 21611011. The next prime is 21611017. The reversal of 21611012 is 21011612.

It is not an unprimeable number, because it can be changed into a prime (21611011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18683 + ... + 19805.

It is an arithmetic number, because the mean of its divisors is an integer number (1675884).

Almost surely, 2^21611012 is an apocalyptic number.

It is an amenable number.

21611012 is a deficient number, since it is larger than the sum of its proper divisors (18610204).

21611012 is a wasteful number, since it uses less digits than its factorization.

21611012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1427 (or 1425 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 14.

The square root of 21611012 is about 4648.7645670651. The cubic root of 21611012 is about 278.5426489914.

Adding to 21611012 its reverse (21011612), we get a palindrome (42622624).

The spelling of 21611012 in words is "twenty-one million, six hundred eleven thousand, twelve".