10999551816 has 160 divisors (see below), whose sum is σ = 34071760800. Its totient is φ = 3287381760.

The previous prime is 10999551793. The next prime is 10999551817. The reversal of 10999551816 is 61815599901.

10999551816 is a `hidden beast` number, since 1 + 0 + 9 + 9 + 9 + 551 + 81 + 6 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (10999551817) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 509775 + ... + 530913.

It is an arithmetic number, because the mean of its divisors is an integer number (212948505).

Almost surely, 2^10999551816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 10999551816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17035880400).

10999551816 is an abundant number, since it is smaller than the sum of its proper divisors (23072208984).

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

10999551816 is a wasteful number, since it uses less digits than its factorization.

10999551816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21241 (or 21228 counting only the distinct ones).

The product of its (nonzero) digits is 874800, while the sum is 54.

The spelling of 10999551816 in words is "ten billion, nine hundred ninety-nine million, five hundred fifty-one thousand, eight hundred sixteen".