13386721401 has 9 divisors (see below), whose sum is σ = 19336876741. Its totient is φ = 8924249532.

The previous prime is 13386721379. The next prime is 13386721421. The reversal of 13386721401 is 10412768331.

It is a happy number.

The square root of 13386721401 is 115701.

It is a perfect power (a square), and thus also a powerful number.

It is a tau number, because it is divible by the number of its divisors (9).

It is a de Polignac number, because none of the positive numbers 2^k-13386721401 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13386721421) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 327820 + ... + 366386.

Almost surely, 2^13386721401 is an apocalyptic number.

13386721401 is the 115701-st square number.

13386721401 is the 57851-st centered octagonal number.

It is an amenable number.

13386721401 is a deficient number, since it is larger than the sum of its proper divisors (5950155340).

13386721401 is an frugal number, since it uses more digits than its factorization.

13386721401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77140 (or 38570 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

Multiplying 13386721401 by its sum of digits (36), we get a square (481921970436 = 694206²).

The spelling of 13386721401 in words is "thirteen billion, three hundred eighty-six million, seven hundred twenty-one thousand, four hundred one".