2121720060157 has 8 divisors (see below), whose sum is σ = 2131101057272. Its totient is φ = 2112343833600.

The previous prime is 2121720060139. The next prime is 2121720060179. The reversal of 2121720060157 is 7510600271212.

It can be written as a sum of positive squares in 4 ways, for example, as 6036357636 + 2115683702521 = 77694^2 + 1454539^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2121720060157 - 2³¹ = 2119572576509 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 (2121720090157) 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 7 ways as a sum of consecutive naturals, for example, 299694 + ... + 2081647.

It is an arithmetic number, because the mean of its divisors is an integer number (266387632159).

Almost surely, 2^{2121720060157} is an apocalyptic number.

It is an amenable number.

2121720060157 is a deficient number, since it is larger than the sum of its proper divisors (9380997115).

2121720060157 is a wasteful number, since it uses less digits than its factorization.

2121720060157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2385279.

The product of its (nonzero) digits is 11760, while the sum is 34.

The spelling of 2121720060157 in words is "two trillion, one hundred twenty-one billion, seven hundred twenty million, sixty thousand, one hundred fifty-seven".