1221251118456 has 16 divisors (see below), whose sum is σ = 3053127796200. Its totient is φ = 407083706144.

The previous prime is 1221251118433. The next prime is 1221251118487. The reversal of 1221251118456 is 6548111521221.

It is a congruent number.

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, 25442731611 + ... + 25442731658.

Almost surely, 2^{1221251118456} is an apocalyptic number.

It is an amenable number.

1221251118456 is an abundant number, since it is smaller than the sum of its proper divisors (1831876677744).

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

1221251118456 is a wasteful number, since it uses less digits than its factorization.

1221251118456 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50885463278 (or 50885463274 counting only the distinct ones).

The product of its digits is 38400, while the sum is 39.

Adding to 1221251118456 its reverse (6548111521221), we get a palindrome (7769362639677).

The spelling of 1221251118456 in words is "one trillion, two hundred twenty-one billion, two hundred fifty-one million, one hundred eighteen thousand, four hundred fifty-six".