9947979811 has 32 divisors (see below), whose sum is σ = 13219476480. Its totient is φ = 7247232000.

The previous prime is 9947979791. The next prime is 9947979817. The reversal of 9947979811 is 1189797499.

It is a cyclic number.

It is not a de Polignac number, because 9947979811 - 2¹⁵ = 9947947043 is a prime.

It is a super-3 number, since 3×9947979811³ (a number of 31 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (9947979817) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 172495 + ... + 222823.

It is an arithmetic number, because the mean of its divisors is an integer number (413108640).

Almost surely, 2^9947979811 is an apocalyptic number.

9947979811 is a deficient number, since it is larger than the sum of its proper divisors (3271496669).

9947979811 is a wasteful number, since it uses less digits than its factorization.

9947979811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50515.

The product of its digits is 10287648, while the sum is 64.

The square root of 9947979811 is about 99739.5599097971. The cubic root of 9947979811 is about 2150.6923900135.

The spelling of 9947979811 in words is "nine billion, nine hundred forty-seven million, nine hundred seventy-nine thousand, eight hundred eleven".