101991292081 has 4 divisors (see below), whose sum is σ = 116561476672. Its totient is φ = 87421107492.

The previous prime is 101991292061. The next prime is 101991292087. The reversal of 101991292081 is 180292199101.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 101991292081 - 2²⁹ = 101454421169 is a prime.

It is a super-2 number, since 2×101991292081² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (101991292087) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7285092285 + ... + 7285092298.

It is an arithmetic number, because the mean of its divisors is an integer number (29140369168).

Almost surely, 2^101991292081 is an apocalyptic number.

It is an amenable number.

101991292081 is a deficient number, since it is larger than the sum of its proper divisors (14570184591).

101991292081 is an equidigital number, since it uses as much as digits as its factorization.

101991292081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14570184590.

The product of its (nonzero) digits is 23328, while the sum is 43.

The spelling of 101991292081 in words is "one hundred one billion, nine hundred ninety-one million, two hundred ninety-two thousand, eighty-one".