1221010944 has 80 divisors (see below), whose sum is σ = 3261487680. Its totient is φ = 405923840.

The previous prime is 1221010943. The next prime is 1221010949. The reversal of 1221010944 is 4490101221.

It is a super-2 number, since 2×1221010944² = 2981735450735542272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221010943) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 753367 + ... + 754985.

It is an arithmetic number, because the mean of its divisors is an integer number (40768596).

Almost surely, 2^1221010944 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221010944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1630743840).

1221010944 is an abundant number, since it is smaller than the sum of its proper divisors (2040476736).

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

1221010944 is an equidigital number, since it uses as much as digits as its factorization.

1221010944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2131 (or 2115 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 24.

The square root of 1221010944 is about 34942.9670176990. The cubic root of 1221010944 is about 1068.8247917564.

The spelling of 1221010944 in words is "one billion, two hundred twenty-one million, ten thousand, nine hundred forty-four".