2145365221520 has 40 divisors (see below), whose sum is σ = 4988179809720. Its totient is φ = 858110704640.

The previous prime is 2145365221511. The next prime is 2145365221543. The reversal of 2145365221520 is 251225635412.

It can be written as a sum of positive squares in 4 ways, for example, as 654338623744 + 1491026597776 = 808912^2 + 1221076^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×2145365221520² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1444250 + ... + 2525190.

It is an arithmetic number, because the mean of its divisors is an integer number (124704495243).

Almost surely, 2^{2145365221520} is an apocalyptic number.

2145365221520 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2145365221520 is an abundant number, since it is smaller than the sum of its proper divisors (2842814588200).

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

2145365221520 is a wasteful number, since it uses less digits than its factorization.

2145365221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105763 (or 1105757 counting only the distinct ones).

The product of its (nonzero) digits is 144000, while the sum is 38.

The spelling of 2145365221520 in words is "two trillion, one hundred forty-five billion, three hundred sixty-five million, two hundred twenty-one thousand, five hundred twenty".