620457561 has 12 divisors (see below), whose sum is σ = 896515620. Its totient is φ = 413500320.

The previous prime is 620457553. The next prime is 620457571. The reversal of 620457561 is 165754026.

It is a happy number.

620457561 is a `hidden beast` number, since 6 + 20 + 4 + 575 + 61 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 243360000 + 377097561 = 15600^2 + 19419^2 .

It is not a de Polignac number, because 620457561 - 2³ = 620457553 is a prime.

It is a super-3 number, since 3×620457561³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (620457571) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22135 + ... + 41603.

It is an arithmetic number, because the mean of its divisors is an integer number (74709635).

Almost surely, 2^620457561 is an apocalyptic number.

It is an amenable number.

620457561 is a deficient number, since it is larger than the sum of its proper divisors (276058059).

620457561 is a wasteful number, since it uses less digits than its factorization.

620457561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23016 (or 23013 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The square root of 620457561 is about 24908.9855473883. The cubic root of 620457561 is about 852.9116118724.

The spelling of 620457561 in words is "six hundred twenty million, four hundred fifty-seven thousand, five hundred sixty-one".