100131557 has 2 divisors, whose sum is σ = 100131558. Its totient is φ = 100131556.

The previous prime is 100131533. The next prime is 100131571. The reversal of 100131557 is 755131001.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 100020001 + 111556 = 10001^2 + 334^2 .

It is an emirp because it is prime and its reverse (755131001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 100131557 - 2¹⁴ = 100115173 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (100133557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50065778 + 50065779.

It is an arithmetic number, because the mean of its divisors is an integer number (50065779).

Almost surely, 2^100131557 is an apocalyptic number.

It is an amenable number.

100131557 is a deficient number, since it is larger than the sum of its proper divisors (1).

100131557 is an equidigital number, since it uses as much as digits as its factorization.

100131557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 525, while the sum is 23.

The square root of 100131557 is about 10006.5756880164. The cubic root of 100131557 is about 464.3623386682.

Adding to 100131557 its reverse (755131001), we get a palindrome (855262558).

The spelling of 100131557 in words is "one hundred million, one hundred thirty-one thousand, five hundred fifty-seven".