551855920 has 160 divisors (see below), whose sum is σ = 1617325056. Its totient is φ = 170112000.

The previous prime is 551855869. The next prime is 551855923. The reversal of 551855920 is 29558155.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (551855923) 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, 621717 + ... + 622603.

Almost surely, 2^551855920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 551855920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (808662528).

551855920 is an abundant number, since it is smaller than the sum of its proper divisors (1065469136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

551855920 is a wasteful number, since it uses less digits than its factorization.

551855920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019 (or 1013 counting only the distinct ones).

The product of its (nonzero) digits is 90000, while the sum is 40.

The square root of 551855920 is about 23491.6138228092. The cubic root of 551855920 is about 820.2418085199.

The spelling of 551855920 in words is "five hundred fifty-one million, eight hundred fifty-five thousand, nine hundred twenty".