1321404304551 has 4 divisors (see below), whose sum is σ = 1761872406072. Its totient is φ = 880936203032.

The previous prime is 1321404304531. The next prime is 1321404304559. The reversal of 1321404304551 is 1554034041231.

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 1321404304551 - 2²³ = 1321395915943 is a prime.

It is a super-2 number, since 2×1321404304551² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321404304559) 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, 220234050756 + ... + 220234050761.

It is an arithmetic number, because the mean of its divisors is an integer number (440468101518).

Almost surely, 2^{1321404304551} is an apocalyptic number.

1321404304551 is a deficient number, since it is larger than the sum of its proper divisors (440468101521).

1321404304551 is an equidigital number, since it uses as much as digits as its factorization.

1321404304551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440468101520.

The product of its (nonzero) digits is 28800, while the sum is 33.

Adding to 1321404304551 its reverse (1554034041231), we get a palindrome (2875438345782).

The spelling of 1321404304551 in words is "one trillion, three hundred twenty-one billion, four hundred four million, three hundred four thousand, five hundred fifty-one".