9991254156 has 48 divisors (see below), whose sum is σ = 25115676768. Its totient is φ = 3073075200.

The previous prime is 9991254113. The next prime is 9991254157. The reversal of 9991254156 is 6514521999.

It is a junction number, because it is equal to n+sod(n) for n = 9991254099 and 9991254108.

It is not an unprimeable number, because it can be changed into a prime (9991254157) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 463866 + ... + 484926.

It is an arithmetic number, because the mean of its divisors is an integer number (523243266).

Almost surely, 2^9991254156 is an apocalyptic number.

It is an amenable number.

9991254156 is an abundant number, since it is smaller than the sum of its proper divisors (15124422612).

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

9991254156 is a wasteful number, since it uses less digits than its factorization.

9991254156 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24122 (or 24120 counting only the distinct ones).

The product of its digits is 874800, while the sum is 51.

The square root of 9991254156 is about 99956.2612145933. The cubic root of 9991254156 is about 2153.8064285168.

The spelling of 9991254156 in words is "nine billion, nine hundred ninety-one million, two hundred fifty-four thousand, one hundred fifty-six".