621212198491 has 2 divisors, whose sum is σ = 621212198492. Its totient is φ = 621212198490.

The previous prime is 621212198447. The next prime is 621212198531. The reversal of 621212198491 is 194891212126.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 621212198491 - 2³¹ = 619064714843 is a prime.

It is not a weakly prime, because it can be changed into another prime (621212198441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310606099245 + 310606099246.

It is an arithmetic number, because the mean of its divisors is an integer number (310606099246).

Almost surely, 2^621212198491 is an apocalyptic number.

621212198491 is a deficient number, since it is larger than the sum of its proper divisors (1).

621212198491 is an equidigital number, since it uses as much as digits as its factorization.

621212198491 is an evil number, because the sum of its binary digits is even.

The product of its digits is 124416, while the sum is 46.

The spelling of 621212198491 in words is "six hundred twenty-one billion, two hundred twelve million, one hundred ninety-eight thousand, four hundred ninety-one".