201531890225 has 24 divisors (see below), whose sum is σ = 262058163960. Its totient is φ = 153533560320.

The previous prime is 201531890177. The next prime is 201531890257. The reversal of 201531890225 is 522098135102.

It can be written as a sum of positive squares in 12 ways, for example, as 15198944656 + 186332945569 = 123284^2 + 431663^2 .

It is a de Polignac number, because none of the positive numbers 2^k-201531890225 is a prime.

It is a super-2 number, since 2×201531890225² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1851014 + ... + 1956863.

It is an arithmetic number, because the mean of its divisors is an integer number (10919090165).

Almost surely, 2^201531890225 is an apocalyptic number.

201531890225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

201531890225 is a deficient number, since it is larger than the sum of its proper divisors (60526273735).

201531890225 is a wasteful number, since it uses less digits than its factorization.

201531890225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3807989 (or 3807984 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 38.

The spelling of 201531890225 in words is "two hundred one billion, five hundred thirty-one million, eight hundred ninety thousand, two hundred twenty-five".