97990120021 has 4 divisors (see below), whose sum is σ = 98022388492. Its totient is φ = 97957851552.

The previous prime is 97990120013. The next prime is 97990120057. The reversal of 97990120021 is 12002109979.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 91053062500 + 6937057521 = 301750^2 + 83289^2 .

It is a cyclic number.

It is not a de Polignac number, because 97990120021 - 2³ = 97990120013 is a prime.

It is a super-3 number, since 3×97990120021³ (a number of 34 digits) contains 333 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 (97990120001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16129680 + ... + 16135753.

It is an arithmetic number, because the mean of its divisors is an integer number (24505597123).

Almost surely, 2^97990120021 is an apocalyptic number.

It is an amenable number.

97990120021 is a deficient number, since it is larger than the sum of its proper divisors (32268471).

97990120021 is a wasteful number, since it uses less digits than its factorization.

97990120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32268470.

The product of its (nonzero) digits is 20412, while the sum is 40.

The spelling of 97990120021 in words is "ninety-seven billion, nine hundred ninety million, one hundred twenty thousand, twenty-one".