1620556623 has 48 divisors (see below), whose sum is σ = 2712393216. Its totient is φ = 913245120.

The previous prime is 1620556601. The next prime is 1620556643. The reversal of 1620556623 is 3266550261.

It is a happy number.

1620556623 is a `hidden beast` number, since 1 + 6 + 20 + 5 + 5 + 6 + 623 = 666.

It is not a de Polignac number, because 1620556623 - 2⁸ = 1620556367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620556643) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2096065 + ... + 2096837.

It is an arithmetic number, because the mean of its divisors is an integer number (56508192).

Almost surely, 2^1620556623 is an apocalyptic number.

1620556623 is a deficient number, since it is larger than the sum of its proper divisors (1091836593).

1620556623 is a wasteful number, since it uses less digits than its factorization.

1620556623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1204 (or 1201 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 36.

The square root of 1620556623 is about 40256.1377059449. The cubic root of 1620556623 is about 1174.5947896249.

The spelling of 1620556623 in words is "one billion, six hundred twenty million, five hundred fifty-six thousand, six hundred twenty-three".