10667721 has 32 divisors (see below), whose sum is σ = 16156800. Its totient is φ = 6220800.

The previous prime is 10667717. The next prime is 10667743. The reversal of 10667721 is 12776601.

10667721 = T₇₈ + T₇₉ + ... + T₄₀₀.

It is a happy number.

It is not a de Polignac number, because 10667721 - 2² = 10667717 is a prime.

It is a super-2 number, since 2×10667721² = 227600542667682, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (10667711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97815 + ... + 97923.

It is an arithmetic number, because the mean of its divisors is an integer number (504900).

Almost surely, 2^10667721 is an apocalyptic number.

It is an amenable number.

10667721 is a deficient number, since it is larger than the sum of its proper divisors (5489079).

10667721 is a wasteful number, since it uses less digits than its factorization.

10667721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 249.

The product of its (nonzero) digits is 3528, while the sum is 30.

The square root of 10667721 is about 3266.1477308903. The cubic root of 10667721 is about 220.1357357956.

The spelling of 10667721 in words is "ten million, six hundred sixty-seven thousand, seven hundred twenty-one".