27861121531 has 2 divisors, whose sum is σ = 27861121532. Its totient is φ = 27861121530.

The previous prime is 27861121489. The next prime is 27861121543. The reversal of 27861121531 is 13512116872.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27861121531 - 2⁷ = 27861121403 is a prime.

It is a super-2 number, since 2×27861121531² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (27861121331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13930560765 + 13930560766.

It is an arithmetic number, because the mean of its divisors is an integer number (13930560766).

Almost surely, 2^27861121531 is an apocalyptic number.

27861121531 is a deficient number, since it is larger than the sum of its proper divisors (1).

27861121531 is an equidigital number, since it uses as much as digits as its factorization.

27861121531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20160, while the sum is 37.

The spelling of 27861121531 in words is "twenty-seven billion, eight hundred sixty-one million, one hundred twenty-one thousand, five hundred thirty-one".