1321563661451 has 6 divisors (see below), whose sum is σ = 1452627826356. Its totient is φ = 1201421510300.

The previous prime is 1321563661387. The next prime is 1321563661469. The reversal of 1321563661451 is 1541663651231.

It is not a de Polignac number, because 1321563661451 - 2⁶ = 1321563661387 is a prime.

It is a super-2 number, since 2×1321563661451² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1321563661471) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5461006745 + ... + 5461006986.

It is an arithmetic number, because the mean of its divisors is an integer number (242104637726).

Almost surely, 2^{1321563661451} is an apocalyptic number.

1321563661451 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1321563661451 is a deficient number, since it is larger than the sum of its proper divisors (131064164905).

1321563661451 is a wasteful number, since it uses less digits than its factorization.

1321563661451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10922013753 (or 10922013742 counting only the distinct ones).

The product of its digits is 388800, while the sum is 44.

The spelling of 1321563661451 in words is "one trillion, three hundred twenty-one billion, five hundred sixty-three million, six hundred sixty-one thousand, four hundred fifty-one".