1213555203443 has 24 divisors (see below), whose sum is σ = 1398380892336. Its totient is φ = 1044301377600.

The previous prime is 1213555203391. The next prime is 1213555203479. The reversal of 1213555203443 is 3443025553121.

It is not a de Polignac number, because 1213555203443 - 2¹² = 1213555199347 is a prime.

It is a super-2 number, since 2×1213555203443² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1213555203397 and 1213555203406.

It is not an unprimeable number, because it can be changed into a prime (1213555203143) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4690853 + ... + 4942793.

It is an arithmetic number, because the mean of its divisors is an integer number (58265870514).

Almost surely, 2^{1213555203443} is an apocalyptic number.

1213555203443 is a deficient number, since it is larger than the sum of its proper divisors (184825688893).

1213555203443 is a wasteful number, since it uses less digits than its factorization.

1213555203443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253203 (or 253184 counting only the distinct ones).

The product of its (nonzero) digits is 216000, while the sum is 38.

The spelling of 1213555203443 in words is "one trillion, two hundred thirteen billion, five hundred fifty-five million, two hundred three thousand, four hundred forty-three".