131511535221 has 16 divisors (see below), whose sum is σ = 191304069120. Its totient is φ = 79697892720.

The previous prime is 131511535201. The next prime is 131511535247. The reversal of 131511535221 is 122535115131.

It is not a de Polignac number, because 131511535221 - 2¹⁰ = 131511534197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131511535201) 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, 309226 + ... + 598868.

It is an arithmetic number, because the mean of its divisors is an integer number (11956504320).

Almost surely, 2^131511535221 is an apocalyptic number.

131511535221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

131511535221 is a deficient number, since it is larger than the sum of its proper divisors (59792533899).

131511535221 is a wasteful number, since it uses less digits than its factorization.

131511535221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303416.

The product of its digits is 4500, while the sum is 30.

The spelling of 131511535221 in words is "one hundred thirty-one billion, five hundred eleven million, five hundred thirty-five thousand, two hundred twenty-one".