11651021 has 4 divisors (see below), whose sum is σ = 11660700. Its totient is φ = 11641344.

The previous prime is 11650981. The next prime is 11651023. The reversal of 11651021 is 12015611.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 4818025 + 6832996 = 2195^2 + 2614^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11651021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11651023) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2726 + ... + 5543.

It is an arithmetic number, because the mean of its divisors is an integer number (2915175).

Almost surely, 2^11651021 is an apocalyptic number.

It is an amenable number.

11651021 is a deficient number, since it is larger than the sum of its proper divisors (9679).

11651021 is an equidigital number, since it uses as much as digits as its factorization.

11651021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9678.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 11651021 is about 3413.3591958656. The cubic root of 11651021 is about 226.7016398842.

Adding to 11651021 its reverse (12015611), we get a palindrome (23666632).

The spelling of 11651021 in words is "eleven million, six hundred fifty-one thousand, twenty-one".