1223641540 has 96 divisors (see below), whose sum is σ = 2894855040. Its totient is φ = 434206080.

The previous prime is 1223641513. The next prime is 1223641547. The reversal of 1223641540 is 451463221.

1223641540 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 1223641499 and 1223641508.

It is not an unprimeable number, because it can be changed into a prime (1223641547) 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, 1144126 + ... + 1145194.

It is an arithmetic number, because the mean of its divisors is an integer number (30154740).

Almost surely, 2^1223641540 is an apocalyptic number.

1223641540 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 1223641540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1447427520).

1223641540 is an abundant number, since it is smaller than the sum of its proper divisors (1671213500).

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

1223641540 is a wasteful number, since it uses less digits than its factorization.

1223641540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1154 (or 1130 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 1223641540 is about 34980.5880453717. The cubic root of 1223641540 is about 1069.5918144911.

It can be divided in two parts, 122364 and 1540, that added together give a square (123904 = 352²).

The spelling of 1223641540 in words is "one billion, two hundred twenty-three million, six hundred forty-one thousand, five hundred forty".