1221380160 has 896 divisors, whose sum is σ = 5505712128. Its totient is φ = 221184000.

The previous prime is 1221380141. The next prime is 1221380161. The reversal of 1221380160 is 610831221.

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

It is a self number, because there is not a number n which added to its sum of digits gives 1221380160.

It is not an unprimeable number, because it can be changed into a prime (1221380161) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 29789740 + ... + 29789780.

It is an arithmetic number, because the mean of its divisors is an integer number (6144768).

Almost surely, 2^1221380160 is an apocalyptic number.

1221380160 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 1221380160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2752856064).

1221380160 is an abundant number, since it is smaller than the sum of its proper divisors (4284331968).

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

1221380160 is a wasteful number, since it uses less digits than its factorization.

1221380160 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123 (or 113 counting only the distinct ones).

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

The square root of 1221380160 is about 34948.2497415822. The cubic root of 1221380160 is about 1068.9325132710.

The spelling of 1221380160 in words is "one billion, two hundred twenty-one million, three hundred eighty thousand, one hundred sixty".