120155188021 has 4 divisors (see below), whose sum is σ = 131078386944. Its totient is φ = 109231989100.

The previous prime is 120155188019. The next prime is 120155188037. The reversal of 120155188021 is 120881551021.

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 120155188021 - 2¹ = 120155188019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (120155188001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5461599445 + ... + 5461599466.

It is an arithmetic number, because the mean of its divisors is an integer number (32769596736).

Almost surely, 2^120155188021 is an apocalyptic number.

120155188021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

120155188021 is a deficient number, since it is larger than the sum of its proper divisors (10923198923).

120155188021 is a wasteful number, since it uses less digits than its factorization.

120155188021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10923198922.

The product of its (nonzero) digits is 6400, while the sum is 34.

The spelling of 120155188021 in words is "one hundred twenty billion, one hundred fifty-five million, one hundred eighty-eight thousand, twenty-one".