23778812521 has 2 divisors, whose sum is σ = 23778812522. Its totient is φ = 23778812520.

The previous prime is 23778812503. The next prime is 23778812567. The reversal of 23778812521 is 12521887732.

It is an a-pointer prime, because the next prime (23778812567) can be obtained adding 23778812521 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17725194496 + 6053618025 = 133136^2 + 77805^2 .

It is a cyclic number.

It is not a de Polignac number, because 23778812521 - 2⁵ = 23778812489 is a prime.

It is not a weakly prime, because it can be changed into another prime (23778812501) 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 as a sum of consecutive naturals, namely, 11889406260 + 11889406261.

It is an arithmetic number, because the mean of its divisors is an integer number (11889406261).

Almost surely, 2^23778812521 is an apocalyptic number.

It is an amenable number.

23778812521 is a deficient number, since it is larger than the sum of its proper divisors (1).

23778812521 is an equidigital number, since it uses as much as digits as its factorization.

23778812521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 376320, while the sum is 46.

The spelling of 23778812521 in words is "twenty-three billion, seven hundred seventy-eight million, eight hundred twelve thousand, five hundred twenty-one".