1318720401 has 24 divisors (see below), whose sum is σ = 1953230760. Its totient is φ = 857016576.

The previous prime is 1318720397. The next prime is 1318720457. The reversal of 1318720401 is 1040278131.

It can be written as a sum of positive squares in 4 ways, for example, as 332697600 + 986022801 = 18240^2 + 31401^2 .

It is not a de Polignac number, because 1318720401 - 2² = 1318720397 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1318720471) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 66085 + ... + 83693.

It is an arithmetic number, because the mean of its divisors is an integer number (81384615).

Almost surely, 2^1318720401 is an apocalyptic number.

It is an amenable number.

1318720401 is a deficient number, since it is larger than the sum of its proper divisors (634510359).

1318720401 is a wasteful number, since it uses less digits than its factorization.

1318720401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17825 (or 17822 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 1318720401 is about 36314.1900777093. The cubic root of 1318720401 is about 1096.6067336153.

Adding to 1318720401 its reverse (1040278131), we get a palindrome (2358998532).

The spelling of 1318720401 in words is "one billion, three hundred eighteen million, seven hundred twenty thousand, four hundred one".