1220573721 has 16 divisors (see below), whose sum is σ = 1687838400. Its totient is φ = 783655488.

The previous prime is 1220573719. The next prime is 1220573743. The reversal of 1220573721 is 1273750221.

It is not a de Polignac number, because 1220573721 - 2¹ = 1220573719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1220553721) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 16870 + ... + 52208.

It is an arithmetic number, because the mean of its divisors is an integer number (105489900).

Almost surely, 2^1220573721 is an apocalyptic number.

It is an amenable number.

1220573721 is a deficient number, since it is larger than the sum of its proper divisors (467264679).

1220573721 is a wasteful number, since it uses less digits than its factorization.

1220573721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35768.

The product of its (nonzero) digits is 5880, while the sum is 30.

The square root of 1220573721 is about 34936.7102200536. The cubic root of 1220573721 is about 1068.6972006063.

The spelling of 1220573721 in words is "one billion, two hundred twenty million, five hundred seventy-three thousand, seven hundred twenty-one".