28121701501 has 2 divisors, whose sum is σ = 28121701502. Its totient is φ = 28121701500.

The previous prime is 28121701493. The next prime is 28121701511. The reversal of 28121701501 is 10510712182.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16549536025 + 11572165476 = 128645^2 + 107574^2 .

It is a cyclic number.

It is not a de Polignac number, because 28121701501 - 2³ = 28121701493 is a prime.

It is a super-2 number, since 2×28121701501² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28121701501.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28121701511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14060850750 + 14060850751.

It is an arithmetic number, because the mean of its divisors is an integer number (14060850751).

Almost surely, 2^28121701501 is an apocalyptic number.

It is an amenable number.

28121701501 is a deficient number, since it is larger than the sum of its proper divisors (1).

28121701501 is an equidigital number, since it uses as much as digits as its factorization.

28121701501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1120, while the sum is 28.

The spelling of 28121701501 in words is "twenty-eight billion, one hundred twenty-one million, seven hundred one thousand, five hundred one".