1973645520 has 720 divisors, whose sum is σ = 8347590720. Its totient is φ = 383201280.

The previous prime is 1973645491. The next prime is 1973645533. The reversal of 1973645520 is 255463791.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 27036204 + ... + 27036276.

It is an arithmetic number, because the mean of its divisors is an integer number (11593876).

Almost surely, 2^1973645520 is an apocalyptic number.

1973645520 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 1973645520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4173795360).

1973645520 is an abundant number, since it is smaller than the sum of its proper divisors (6373945200).

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

1973645520 is a wasteful number, since it uses less digits than its factorization.

1973645520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 226800, while the sum is 42.

The square root of 1973645520 is about 44425.7303822908. The cubic root of 1973645520 is about 1254.3624683180.

It can be divided in two parts, 19736 and 45520, that added together give a palindrome (65256).

The spelling of 1973645520 in words is "one billion, nine hundred seventy-three million, six hundred forty-five thousand, five hundred twenty".