11400021 has 10 divisors (see below), whose sum is σ = 17029782. Its totient is φ = 7599960.

The previous prime is 11400017. The next prime is 11400043. The reversal of 11400021 is 12000411.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 9696996 + 1703025 = 3114^2 + 1305^2 .

It is not a de Polignac number, because 11400021 - 2² = 11400017 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 11399976 and 11400012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11400071) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 70290 + ... + 70451.

Almost surely, 2^11400021 is an apocalyptic number.

It is an amenable number.

11400021 is a deficient number, since it is larger than the sum of its proper divisors (5629761).

11400021 is an equidigital number, since it uses as much as digits as its factorization.

11400021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140753 (or 140744 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 11400021 is about 3376.3917130570. The cubic root of 11400021 is about 225.0618496634.

Adding to 11400021 its reverse (12000411), we get a palindrome (23400432).

The spelling of 11400021 in words is "eleven million, four hundred thousand, twenty-one".