21122222012 has 6 divisors (see below), whose sum is σ = 36963888528. Its totient is φ = 10561111004.

The previous prime is 21122221973. The next prime is 21122222057. The reversal of 21122222012 is 21022222112.

It is a happy number.

It is a super-2 number, since 2×21122222012² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2640277748 + ... + 2640277755.

It is an arithmetic number, because the mean of its divisors is an integer number (6160648088).

Almost surely, 2^21122222012 is an apocalyptic number.

It is an amenable number.

21122222012 is a deficient number, since it is larger than the sum of its proper divisors (15841666516).

21122222012 is a wasteful number, since it uses less digits than its factorization.

21122222012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5280555507 (or 5280555505 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21122222012 its reverse (21022222112), we get a palindrome (42144444124).

The spelling of 21122222012 in words is "twenty-one billion, one hundred twenty-two million, two hundred twenty-two thousand, twelve".