621051491 has 2 divisors, whose sum is σ = 621051492. Its totient is φ = 621051490.

The previous prime is 621051479. The next prime is 621051533. The reversal of 621051491 is 194150126.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-621051491 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (621053491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310525745 + 310525746.

It is an arithmetic number, because the mean of its divisors is an integer number (310525746).

Almost surely, 2^621051491 is an apocalyptic number.

621051491 is a deficient number, since it is larger than the sum of its proper divisors (1).

621051491 is an equidigital number, since it uses as much as digits as its factorization.

621051491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 621051491 is about 24920.9046986661. The cubic root of 621051491 is about 853.1836735863.

The spelling of 621051491 in words is "six hundred twenty-one million, fifty-one thousand, four hundred ninety-one".