13401721642 has 4 divisors (see below), whose sum is σ = 20102582466. Its totient is φ = 6700860820.

The previous prime is 13401721637. The next prime is 13401721643. The reversal of 13401721642 is 24612710431.

13401721642 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in only one way, i.e., 13046436841 + 355284801 = 114221^2 + 18849^2 .

It is a super-2 number, since 2×13401721642² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (13401721643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3350430409 + ... + 3350430412.

Almost surely, 2^13401721642 is an apocalyptic number.

13401721642 is a deficient number, since it is larger than the sum of its proper divisors (6700860824).

13401721642 is an equidigital number, since it uses as much as digits as its factorization.

13401721642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6700860823.

The product of its (nonzero) digits is 8064, while the sum is 31.

The spelling of 13401721642 in words is "thirteen billion, four hundred one million, seven hundred twenty-one thousand, six hundred forty-two".