28599973621 has 2 divisors, whose sum is σ = 28599973622. Its totient is φ = 28599973620.

The previous prime is 28599973603. The next prime is 28599973637. The reversal of 28599973621 is 12637999582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 28363275396 + 236698225 = 168414^2 + 15385^2 .

It is a cyclic number.

It is not a de Polignac number, because 28599973621 - 2⁹ = 28599973109 is a prime.

It is a super-2 number, since 2×28599973621² (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 28599973621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (28599973651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14299986810 + 14299986811.

It is an arithmetic number, because the mean of its divisors is an integer number (14299986811).

Almost surely, 2^28599973621 is an apocalyptic number.

It is an amenable number.

28599973621 is a deficient number, since it is larger than the sum of its proper divisors (1).

28599973621 is an equidigital number, since it uses as much as digits as its factorization.

28599973621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 14696640, while the sum is 61.

The spelling of 28599973621 in words is "twenty-eight billion, five hundred ninety-nine million, nine hundred seventy-three thousand, six hundred twenty-one".