1223145520 has 160 divisors (see below), whose sum is σ = 3181939200. Its totient is φ = 435105792.

The previous prime is 1223145493. The next prime is 1223145523. The reversal of 1223145520 is 255413221.

It is not an unprimeable number, because it can be changed into a prime (1223145523) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2062344 + ... + 2062936.

It is an arithmetic number, because the mean of its divisors is an integer number (19887120).

Almost surely, 2^1223145520 is an apocalyptic number.

1223145520 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 1223145520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1590969600).

1223145520 is an abundant number, since it is smaller than the sum of its proper divisors (1958793680).

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

1223145520 is a wasteful number, since it uses less digits than its factorization.

1223145520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 707 (or 701 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 25.

The square root of 1223145520 is about 34973.4973944557. The cubic root of 1223145520 is about 1069.4472703530.

Adding to 1223145520 its reverse (255413221), we get a palindrome (1478558741).

The spelling of 1223145520 in words is "one billion, two hundred twenty-three million, one hundred forty-five thousand, five hundred twenty".