621984949 has 4 divisors (see below), whose sum is σ = 622904364. Its totient is φ = 621065536.

The previous prime is 621984943. The next prime is 621984971. The reversal of 621984949 is 949489126.

621984949 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 949489126 = 2 ⋅474744563.

It can be written as a sum of positive squares in 2 ways, for example, as 572070724 + 49914225 = 23918^2 + 7065^2 .

It is a cyclic number.

It is not a de Polignac number, because 621984949 - 2¹⁷ = 621853877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 621984896 and 621984905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (621984943) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 458692 + ... + 460045.

It is an arithmetic number, because the mean of its divisors is an integer number (155726091).

Almost surely, 2^621984949 is an apocalyptic number.

It is an amenable number.

621984949 is a deficient number, since it is larger than the sum of its proper divisors (919415).

621984949 is an equidigital number, since it uses as much as digits as its factorization.

621984949 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 919414.

The product of its digits is 1119744, while the sum is 52.

The square root of 621984949 is about 24939.6260797952. The cubic root of 621984949 is about 853.6109126910.

The spelling of 621984949 in words is "six hundred twenty-one million, nine hundred eighty-four thousand, nine hundred forty-nine".