11285721 has 6 divisors (see below), whose sum is σ = 16301610. Its totient is φ = 7523808.

The previous prime is 11285717. The next prime is 11285723. The reversal of 11285721 is 12758211.

11285721 is digitally balanced in base 2 and base 4, because in such bases it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 10653696 + 632025 = 3264^2 + 795^2 .

It is not a de Polignac number, because 11285721 - 2² = 11285717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (11285723) 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, 626976 + ... + 626993.

It is an arithmetic number, because the mean of its divisors is an integer number (2716935).

Almost surely, 2^11285721 is an apocalyptic number.

It is an amenable number.

11285721 is a deficient number, since it is larger than the sum of its proper divisors (5015889).

11285721 is a wasteful number, since it uses less digits than its factorization.

11285721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253975 (or 1253972 counting only the distinct ones).

The product of its digits is 1120, while the sum is 27.

The square root of 11285721 is about 3359.4227182657. The cubic root of 11285721 is about 224.3071427030.

The spelling of 11285721 in words is "eleven million, two hundred eighty-five thousand, seven hundred twenty-one".