623522621 has 4 divisors (see below), whose sum is σ = 627126972. Its totient is φ = 619918272.

The previous prime is 623522611. The next prime is 623522657. The reversal of 623522621 is 126225326.

623522621 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: 126225326 = 2 ⋅63112663.

It can be written as a sum of positive squares in 2 ways, for example, as 264420121 + 359102500 = 16261^2 + 18950^2 .

It is a cyclic number.

It is not a de Polignac number, because 623522621 - 2¹⁴ = 623506237 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623522611) 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, 1801916 + ... + 1802261.

It is an arithmetic number, because the mean of its divisors is an integer number (156781743).

Almost surely, 2^623522621 is an apocalyptic number.

It is an amenable number.

623522621 is a deficient number, since it is larger than the sum of its proper divisors (3604351).

623522621 is a wasteful number, since it uses less digits than its factorization.

623522621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3604350.

The product of its digits is 8640, while the sum is 29.

The square root of 623522621 is about 24970.4349381423. The cubic root of 623522621 is about 854.3137664797.

Adding to 623522621 its reverse (126225326), we get a palindrome (749747947).

The spelling of 623522621 in words is "six hundred twenty-three million, five hundred twenty-two thousand, six hundred twenty-one".