620263781 has 2 divisors, whose sum is σ = 620263782. Its totient is φ = 620263780.

The previous prime is 620263771. The next prime is 620263789. The reversal of 620263781 is 187362026.

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., 346890625 + 273373156 = 18625^2 + 16534^2 .

It is a cyclic number.

It is not a de Polignac number, because 620263781 - 2¹⁰ = 620262757 is a prime.

It is a super-2 number, since 2×620263781² = 769454316040831922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (620263789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 310131890 + 310131891.

It is an arithmetic number, because the mean of its divisors is an integer number (310131891).

Almost surely, 2^620263781 is an apocalyptic number.

It is an amenable number.

620263781 is a deficient number, since it is larger than the sum of its proper divisors (1).

620263781 is an equidigital number, since it uses as much as digits as its factorization.

620263781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24192, while the sum is 35.

The square root of 620263781 is about 24905.0954826517. The cubic root of 620263781 is about 852.8228094402.

The spelling of 620263781 in words is "six hundred twenty million, two hundred sixty-three thousand, seven hundred eighty-one".