201551020 has 24 divisors (see below), whose sum is σ = 461735568. Its totient is φ = 73291200.

The previous prime is 201551011. The next prime is 201551027. The reversal of 201551020 is 20155102.

It is a junction number, because it is equal to n+sod(n) for n = 201550985 and 201551003.

It is not an unprimeable number, because it can be changed into a prime (201551027) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 457851 + ... + 458290.

It is an arithmetic number, because the mean of its divisors is an integer number (19238982).

Almost surely, 2^201551020 is an apocalyptic number.

201551020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201551020 is an abundant number, since it is smaller than the sum of its proper divisors (260184548).

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

201551020 is a wasteful number, since it uses less digits than its factorization.

201551020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 916161 (or 916159 counting only the distinct ones).

The product of its (nonzero) digits is 100, while the sum is 16.

The square root of 201551020 is about 14196.8665556876. The cubic root of 201551020 is about 586.3113931672.

It can be divided in two parts, 2015 and 51020, that added together give a palindrome (53035).

The spelling of 201551020 in words is "two hundred one million, five hundred fifty-one thousand, twenty".