620677684561 has 45 divisors (see below), whose sum is σ = 727163474155. Its totient is φ = 529674537920.

The previous prime is 620677684553. The next prime is 620677684567. The reversal of 620677684561 is 165486776026.

The square root of 620677684561 is 787831.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 483226571025 + 137451113536 = 695145^2 + 370744^2 .

It is not a de Polignac number, because 620677684561 - 2³ = 620677684553 is a prime.

It is a super-2 number, since 2×620677684561² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 620677684496 and 620677684505.

It is not an unprimeable number, because it can be changed into a prime (620677684567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 1620568176 + ... + 1620568558.

Almost surely, 2^620677684561 is an apocalyptic number.

620677684561 is the 787831-st square number.

620677684561 is the 393916-th centered octagonal number.

It is an amenable number.

620677684561 is a deficient number, since it is larger than the sum of its proper divisors (106485789594).

620677684561 is an frugal number, since it uses more digits than its factorization.

620677684561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 844 (or 411 counting only the distinct ones).

The product of its (nonzero) digits is 20321280, while the sum is 58.

The spelling of 620677684561 in words is "six hundred twenty billion, six hundred seventy-seven million, six hundred eighty-four thousand, five hundred sixty-one".