11951557 has 2 divisors, whose sum is σ = 11951558. Its totient is φ = 11951556.

The previous prime is 11951531. The next prime is 11951591. The reversal of 11951557 is 75515911.

It is a happy number.

It is an a-pointer prime, because the next prime (11951591) can be obtained adding 11951557 to its sum of digits (34).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11792356 + 159201 = 3434^2 + 399^2 .

It is an emirp because it is prime and its reverse (75515911) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 11951557 - 2¹⁵ = 11918789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11951507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5975778 + 5975779.

It is an arithmetic number, because the mean of its divisors is an integer number (5975779).

Almost surely, 2^11951557 is an apocalyptic number.

It is an amenable number.

11951557 is a deficient number, since it is larger than the sum of its proper divisors (1).

11951557 is an equidigital number, since it uses as much as digits as its factorization.

11951557 is an evil number, because the sum of its binary digits is even.

The product of its digits is 7875, while the sum is 34.

The square root of 11951557 is about 3457.1023994091. The cubic root of 11951557 is about 228.6343586212.

The spelling of 11951557 in words is "eleven million, nine hundred fifty-one thousand, five hundred fifty-seven".