621306773 has 2 divisors, whose sum is σ = 621306774. Its totient is φ = 621306772.

The previous prime is 621306739. The next prime is 621306779. The reversal of 621306773 is 377603126.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 558944164 + 62362609 = 23642^2 + 7897^2 .

It is a cyclic number.

It is not a de Polignac number, because 621306773 - 2¹² = 621302677 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (621306779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310653386 + 310653387.

It is an arithmetic number, because the mean of its divisors is an integer number (310653387).

Almost surely, 2^621306773 is an apocalyptic number.

It is an amenable number.

621306773 is a deficient number, since it is larger than the sum of its proper divisors (1).

621306773 is an equidigital number, since it uses as much as digits as its factorization.

621306773 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31752, while the sum is 35.

The square root of 621306773 is about 24926.0260169968. The cubic root of 621306773 is about 853.3005573993.

Adding to 621306773 its reverse (377603126), we get a palindrome (998909899).

The spelling of 621306773 in words is "six hundred twenty-one million, three hundred six thousand, seven hundred seventy-three".