1213553205444 has 12 divisors (see below), whose sum is σ = 2831624146064. Its totient is φ = 404517735144.

The previous prime is 1213553205421. The next prime is 1213553205457. The reversal of 1213553205444 is 4445023553121.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×1213553205444² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50564716882 + ... + 50564716905.

Almost surely, 2^{1213553205444} is an apocalyptic number.

It is an amenable number.

1213553205444 is an abundant number, since it is smaller than the sum of its proper divisors (1618070940620).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1213553205444 is a wasteful number, since it uses less digits than its factorization.

1213553205444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 101129433794 (or 101129433792 counting only the distinct ones).

The product of its (nonzero) digits is 288000, while the sum is 39.

Adding to 1213553205444 its reverse (4445023553121), we get a palindrome (5658576758565).

The spelling of 1213553205444 in words is "one trillion, two hundred thirteen billion, five hundred fifty-three million, two hundred five thousand, four hundred forty-four".