1221072760 has 64 divisors (see below), whose sum is σ = 2901588480. Its totient is φ = 461535360.

The previous prime is 1221072757. The next prime is 1221072761. The reversal of 1221072760 is 672701221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221072761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68365 + ... + 84355.

It is an arithmetic number, because the mean of its divisors is an integer number (45337320).

Almost surely, 2^1221072760 is an apocalyptic number.

1221072760 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221072760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1450794240).

1221072760 is an abundant number, since it is smaller than the sum of its proper divisors (1680515720).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221072760 is a wasteful number, since it uses less digits than its factorization.

1221072760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16108 (or 16104 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 1221072760 is about 34943.8515335674. The cubic root of 1221072760 is about 1068.8428285476.

Adding to 1221072760 its reverse (672701221), we get a palindrome (1893773981).

The spelling of 1221072760 in words is "one billion, two hundred twenty-one million, seventy-two thousand, seven hundred sixty".