11517421 has 6 divisors (see below), whose sum is σ = 11793390. Its totient is φ = 11247768.

The previous prime is 11517413. The next prime is 11517427. The reversal of 11517421 is 12471511.

It can be written as a sum of positive squares in only one way, i.e., 9853321 + 1664100 = 3139^2 + 1290^2 .

It is not a de Polignac number, because 11517421 - 2³ = 11517413 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11517392 and 11517401.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11517427) 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, 1266 + ... + 4963.

It is an arithmetic number, because the mean of its divisors is an integer number (1965565).

Almost surely, 2^11517421 is an apocalyptic number.

It is an amenable number.

11517421 is a deficient number, since it is larger than the sum of its proper divisors (275969).

11517421 is an frugal number, since it uses more digits than its factorization.

11517421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6315 (or 6272 counting only the distinct ones).

The product of its digits is 280, while the sum is 22.

The square root of 11517421 is about 3393.7326058486. The cubic root of 11517421 is about 225.8317919797.

Adding to 11517421 its reverse (12471511), we get a palindrome (23988932).

The spelling of 11517421 in words is "eleven million, five hundred seventeen thousand, four hundred twenty-one".