1213664221064 has 24 divisors (see below), whose sum is σ = 2351395510830. Its totient is φ = 587256877440.

The previous prime is 1213664220943. The next prime is 1213664221067. The reversal of 1213664221064 is 4601224663121.

It can be written as a sum of positive squares in only one way, i.e., 1131793844164 + 81870376900 = 1063858^2 + 286130^2 .

It is a super-2 number, since 2×1213664221064² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1213664221067) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 78924689 + ... + 78940064.

Almost surely, 2^{1213664221064} is an apocalyptic number.

It is an amenable number.

1213664221064 is a deficient number, since it is larger than the sum of its proper divisors (1137731289766).

1213664221064 is a wasteful number, since it uses less digits than its factorization.

1213664221064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157864821 (or 157864786 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 38.

Adding to 1213664221064 its reverse (4601224663121), we get a palindrome (5814888884185).

The spelling of 1213664221064 in words is "one trillion, two hundred thirteen billion, six hundred sixty-four million, two hundred twenty-one thousand, sixty-four".