1821516788608 has 64 divisors (see below), whose sum is σ = 3959683770240. Its totient is φ = 827755200000.

The previous prime is 1821516788603. The next prime is 1821516788617. The reversal of 1821516788608 is 8068876151281.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×1821516788608² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1821516788603) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5544133 + ... + 5863483.

It is an arithmetic number, because the mean of its divisors is an integer number (61870058910).

Almost surely, 2^{1821516788608} is an apocalyptic number.

It is an amenable number.

1821516788608 is an abundant number, since it is smaller than the sum of its proper divisors (2138166981632).

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

1821516788608 is a wasteful number, since it uses less digits than its factorization.

1821516788608 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323427 (or 323415 counting only the distinct ones).

The product of its (nonzero) digits is 10321920, while the sum is 61.

The spelling of 1821516788608 in words is "one trillion, eight hundred twenty-one billion, five hundred sixteen million, seven hundred eighty-eight thousand, six hundred eight".