99945212220 has 144 divisors (see below), whose sum is σ = 346715328960. Its totient is φ = 22828889088.

The previous prime is 99945212197. The next prime is 99945212231. The reversal of 99945212220 is 2221254999.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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 47 ways as a sum of consecutive naturals, for example, 1854616 + ... + 1907744.

It is an arithmetic number, because the mean of its divisors is an integer number (2407745340).

Almost surely, 2^99945212220 is an apocalyptic number.

99945212220 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 99945212220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173357664480).

99945212220 is an abundant number, since it is smaller than the sum of its proper divisors (246770116740).

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

99945212220 is a wasteful number, since it uses less digits than its factorization.

99945212220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54644 (or 54639 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 45.

The spelling of 99945212220 in words is "ninety-nine billion, nine hundred forty-five million, two hundred twelve thousand, two hundred twenty".