1221373260 has 72 divisors (see below), whose sum is σ = 3733185456. Its totient is φ = 323207040.

The previous prime is 1221373213. The next prime is 1221373271. The reversal of 1221373260 is 623731221.

1221373260 is a `hidden beast` number, since 12 + 21 + 373 + 260 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2319 + ... + 49478.

It is an arithmetic number, because the mean of its divisors is an integer number (51849798).

Almost surely, 2^1221373260 is an apocalyptic number.

1221373260 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 1221373260, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1866592728).

1221373260 is an abundant number, since it is smaller than the sum of its proper divisors (2511812196).

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

1221373260 is a wasteful number, since it uses less digits than its factorization.

1221373260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51943 (or 51938 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 1221373260 is about 34948.1510240528. The cubic root of 1221373260 is about 1068.9305003437.

The spelling of 1221373260 in words is "one billion, two hundred twenty-one million, three hundred seventy-three thousand, two hundred sixty".