1221040052431 has 4 divisors (see below), whose sum is σ = 1241735646600. Its totient is φ = 1200344458264.

The previous prime is 1221040052411. The next prime is 1221040052443. The reversal of 1221040052431 is 1342500401221.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1221040052431 - 2⁷ = 1221040052303 is a prime.

It is a super-2 number, since 2×1221040052431² (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 = 1221040052396 and 1221040052405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221040052411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10347796996 + ... + 10347797113.

It is an arithmetic number, because the mean of its divisors is an integer number (310433911650).

Almost surely, 2^{1221040052431} is an apocalyptic number.

1221040052431 is a deficient number, since it is larger than the sum of its proper divisors (20695594169).

1221040052431 is an equidigital number, since it uses as much as digits as its factorization.

1221040052431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20695594168.

The product of its (nonzero) digits is 1920, while the sum is 25.

Adding to 1221040052431 its reverse (1342500401221), we get a palindrome (2563540453652).

The spelling of 1221040052431 in words is "one trillion, two hundred twenty-one billion, forty million, fifty-two thousand, four hundred thirty-one".