621556250129 has 2 divisors, whose sum is σ = 621556250130. Its totient is φ = 621556250128.

The previous prime is 621556250083. The next prime is 621556250141. The reversal of 621556250129 is 921052655126.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 366684747025 + 254871503104 = 605545^2 + 504848^2 .

It is a cyclic number.

It is not a de Polignac number, because 621556250129 - 2¹² = 621556246033 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 621556250129.

It is not a weakly prime, because it can be changed into another prime (621556250429) 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, 310778125064 + 310778125065.

It is an arithmetic number, because the mean of its divisors is an integer number (310778125065).

Almost surely, 2^621556250129 is an apocalyptic number.

It is an amenable number.

621556250129 is a deficient number, since it is larger than the sum of its proper divisors (1).

621556250129 is an equidigital number, since it uses as much as digits as its factorization.

621556250129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324000, while the sum is 44.

The spelling of 621556250129 in words is "six hundred twenty-one billion, five hundred fifty-six million, two hundred fifty thousand, one hundred twenty-nine".