920644563 has 16 divisors (see below), whose sum is σ = 1296721280. Its totient is φ = 579394944.

The previous prime is 920644559. The next prime is 920644579. The reversal of 920644563 is 365446029.

It is not a de Polignac number, because 920644563 - 2² = 920644559 is a prime.

It is a super-2 number, since 2×920644563² = 1695172822762921938, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (920644523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12406 + ... + 44667.

It is an arithmetic number, because the mean of its divisors is an integer number (81045080).

Almost surely, 2^920644563 is an apocalyptic number.

920644563 is a deficient number, since it is larger than the sum of its proper divisors (376076717).

920644563 is a wasteful number, since it uses less digits than its factorization.

920644563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57378.

The product of its (nonzero) digits is 155520, while the sum is 39.

The square root of 920644563 is about 30342.1252222055. The cubic root of 920644563 is about 972.8159089816.

The spelling of 920644563 in words is "nine hundred twenty million, six hundred forty-four thousand, five hundred sixty-three".