21002612 has 24 divisors (see below), whose sum is σ = 38206560. Its totient is φ = 10090080.

The previous prime is 21002591. The next prime is 21002621. The reversal of 21002612 is 21620012.

It is a super-2 number, since 2×21002612² = 882219421645088, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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, 38123 + ... + 38669.

It is an arithmetic number, because the mean of its divisors is an integer number (1591940).

Almost surely, 2^21002612 is an apocalyptic number.

It is an amenable number.

21002612 is a deficient number, since it is larger than the sum of its proper divisors (17203948).

21002612 is a wasteful number, since it uses less digits than its factorization.

21002612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 911 (or 909 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 21002612 is about 4582.8606786591. The cubic root of 21002612 is about 275.9038557511.

Adding to 21002612 its reverse (21620012), we get a palindrome (42622624).

The spelling of 21002612 in words is "twenty-one million, two thousand, six hundred twelve".