990865612800 has 2520 divisors, whose sum is σ = 4539628904976. Its totient is φ = 212548976640.

The previous prime is 990865612783. The next prime is 990865612801. The reversal of 990865612800 is 8216568099.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (2520).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990865612801) by changing a digit.

It is a polite number, since it can be written in 179 ways as a sum of consecutive naturals, for example, 18695577574 + ... + 18695577626.

Almost surely, 2^990865612800 is an apocalyptic number.

990865612800 is a gapful number since it is divisible by the number (90) 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 990865612800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2269814452488).

990865612800 is an abundant number, since it is smaller than the sum of its proper divisors (3548763292176).

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

990865612800 is a wasteful number, since it uses less digits than its factorization.

990865612800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138 (or 93 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 54.

The spelling of 990865612800 in words is "nine hundred ninety billion, eight hundred sixty-five million, six hundred twelve thousand, eight hundred".