990155550101 has 4 divisors (see below), whose sum is σ = 996230124192. Its totient is φ = 984080976012.

The previous prime is 990155550073. The next prime is 990155550151. The reversal of 990155550101 is 101055551099.

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 a de Polignac number, because none of the positive numbers 2^k-990155550101 is a prime.

It is a super-2 number, since 2×990155550101² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990155550151) 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, 3037286801 + ... + 3037287126.

It is an arithmetic number, because the mean of its divisors is an integer number (249057531048).

Almost surely, 2^990155550101 is an apocalyptic number.

It is an amenable number.

990155550101 is a deficient number, since it is larger than the sum of its proper divisors (6074574091).

990155550101 is a wasteful number, since it uses less digits than its factorization.

990155550101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6074574090.

The product of its (nonzero) digits is 50625, while the sum is 41.

The spelling of 990155550101 in words is "nine hundred ninety billion, one hundred fifty-five million, five hundred fifty thousand, one hundred one".