6991203138120 has 256 divisors, whose sum is σ = 24175928736000. Its totient is φ = 1794931826688.

The previous prime is 6991203138103. The next prime is 6991203138121. The reversal of 6991203138120 is 218313021996.

It is a happy number.

6991203138120 is a `hidden beast` number, since 6 + 99 + 120 + 313 + 8 + 120 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (6991203138121) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 10739787 + ... + 11372133.

It is an arithmetic number, because the mean of its divisors is an integer number (94437221625).

Almost surely, 2^{6991203138120} is an apocalyptic number.

6991203138120 is a gapful number since it is divisible by the number (60) 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 6991203138120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12087964368000).

6991203138120 is an abundant number, since it is smaller than the sum of its proper divisors (17184725597880).

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

6991203138120 is a wasteful number, since it uses less digits than its factorization.

6991203138120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 632749 (or 632739 counting only the distinct ones).

The product of its (nonzero) digits is 139968, while the sum is 45.

The spelling of 6991203138120 in words is "six trillion, nine hundred ninety-one billion, two hundred three million, one hundred thirty-eight thousand, one hundred twenty".