99921264660 has 288 divisors, whose sum is σ = 360861376512. Its totient is φ = 22735002240.

The previous prime is 99921264647. The next prime is 99921264757. The reversal of 99921264660 is 6646212999.

It is a happy number.

99921264660 is a `hidden beast` number, since 99 + 92 + 1 + 2 + 6 + 466 + 0 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 99921264597 and 99921264606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 7579875 + ... + 7593045.

Almost surely, 2^99921264660 is an apocalyptic number.

99921264660 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

99921264660 is the 158052-nd decagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 99921264660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (180430688256).

99921264660 is an abundant number, since it is smaller than the sum of its proper divisors (260940111852).

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

99921264660 is a wasteful number, since it uses less digits than its factorization.

99921264660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13425 (or 13411 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The spelling of 99921264660 in words is "ninety-nine billion, nine hundred twenty-one million, two hundred sixty-four thousand, six hundred sixty".