28503780061 has 4 divisors (see below), whose sum is σ = 28905241824. Its totient is φ = 28102318300.

The previous prime is 28503780049. The next prime is 28503780073. The reversal of 28503780061 is 16008730582.

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 an interprime number because it is at equal distance from previous prime (28503780049) and next prime (28503780073).

It is not a de Polignac number, because 28503780061 - 2⁵ = 28503780029 is a prime.

It is a super-2 number, since 2×28503780061² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28503779996 and 28503780023.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28503780661) 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, 200730775 + ... + 200730916.

It is an arithmetic number, because the mean of its divisors is an integer number (7226310456).

Almost surely, 2^28503780061 is an apocalyptic number.

It is an amenable number.

28503780061 is a deficient number, since it is larger than the sum of its proper divisors (401461763).

28503780061 is an equidigital number, since it uses as much as digits as its factorization.

28503780061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401461762.

The product of its (nonzero) digits is 80640, while the sum is 40.

The spelling of 28503780061 in words is "twenty-eight billion, five hundred three million, seven hundred eighty thousand, sixty-one".