21015512201612 has 24 divisors (see below), whose sum is σ = 37717805043072. Its totient is φ = 10239590422400.

The previous prime is 21015512201611. The next prime is 21015512201617. The reversal of 21015512201612 is 21610221551012.

It is a super-2 number, since 2×21015512201612² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21015512201611) 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, 74101439 + ... + 74384502.

It is an arithmetic number, because the mean of its divisors is an integer number (1571575210128).

Almost surely, 2^{21015512201612} is an apocalyptic number.

It is an amenable number.

21015512201612 is a deficient number, since it is larger than the sum of its proper divisors (16702292841460).

21015512201612 is a wasteful number, since it uses less digits than its factorization.

21015512201612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 148486849 (or 148486847 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 29.

Adding to 21015512201612 its reverse (21610221551012), we get a palindrome (42625733752624).

The spelling of 21015512201612 in words is "twenty-one trillion, fifteen billion, five hundred twelve million, two hundred one thousand, six hundred twelve".