1620855863 has 32 divisors (see below), whose sum is σ = 1859303424. Its totient is φ = 1411344000.

The previous prime is 1620855853. The next prime is 1620855869. The reversal of 1620855863 is 3685580261.

It is not a de Polignac number, because 1620855863 - 2⁶ = 1620855799 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1620855869) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6725423 + ... + 6725663.

It is an arithmetic number, because the mean of its divisors is an integer number (58103232).

Almost surely, 2^1620855863 is an apocalyptic number.

1620855863 is a deficient number, since it is larger than the sum of its proper divisors (238447561).

1620855863 is a wasteful number, since it uses less digits than its factorization.

1620855863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468 (or 446 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 44.

The square root of 1620855863 is about 40259.8542347088. The cubic root of 1620855863 is about 1174.6670825041.

The spelling of 1620855863 in words is "one billion, six hundred twenty million, eight hundred fifty-five thousand, eight hundred sixty-three".