11681553 has 8 divisors (see below), whose sum is σ = 16773568. Its totient is φ = 7188624.

The previous prime is 11681543. The next prime is 11681557. The reversal of 11681553 is 35518611.

11681553 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 11681553 - 2⁶ = 11681489 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11681553.

It is not an unprimeable number, because it can be changed into a prime (11681557) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149725 + ... + 149802.

It is an arithmetic number, because the mean of its divisors is an integer number (2096696).

Almost surely, 2^11681553 is an apocalyptic number.

11681553 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

11681553 is a deficient number, since it is larger than the sum of its proper divisors (5092015).

11681553 is a wasteful number, since it uses less digits than its factorization.

11681553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299543.

The product of its digits is 3600, while the sum is 30.

The square root of 11681553 is about 3417.8286967020. The cubic root of 11681553 is about 226.8994942781.

The spelling of 11681553 in words is "eleven million, six hundred eighty-one thousand, five hundred fifty-three".