1121016721 has 12 divisors (see below), whose sum is σ = 1274685300. Its totient is φ = 983961440.

The previous prime is 1121016719. The next prime is 1121016733. The reversal of 1121016721 is 1276101211.

It can be written as a sum of positive squares in 2 ways, for example, as 891918225 + 229098496 = 29865^2 + 15136^2 .

It is not a de Polignac number, because 1121016721 - 2¹ = 1121016719 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1121016692 and 1121016701.

It is not an unprimeable number, because it can be changed into a prime (1121016821) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 156226 + ... + 163243.

It is an arithmetic number, because the mean of its divisors is an integer number (106223775).

Almost surely, 2^1121016721 is an apocalyptic number.

1121016721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1121016721 is a deficient number, since it is larger than the sum of its proper divisors (153668579).

1121016721 is a wasteful number, since it uses less digits than its factorization.

1121016721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 319520 (or 319509 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 22.

The square root of 1121016721 is about 33481.5877909038. The cubic root of 1121016721 is about 1038.8129704359.

Adding to 1121016721 its reverse (1276101211), we get a palindrome (2397117932).

The spelling of 1121016721 in words is "one billion, one hundred twenty-one million, sixteen thousand, seven hundred twenty-one".