61505005531 has 2 divisors, whose sum is σ = 61505005532. Its totient is φ = 61505005530.

The previous prime is 61505005477. The next prime is 61505005561. The reversal of 61505005531 is 13550050516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61505005531 - 2¹³ = 61504997339 is a prime.

It is a super-2 number, since 2×61505005531² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 61505005493 and 61505005502.

It is not a weakly prime, because it can be changed into another prime (61505005561) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30752502765 + 30752502766.

It is an arithmetic number, because the mean of its divisors is an integer number (30752502766).

Almost surely, 2^61505005531 is an apocalyptic number.

61505005531 is a deficient number, since it is larger than the sum of its proper divisors (1).

61505005531 is an equidigital number, since it uses as much as digits as its factorization.

61505005531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11250, while the sum is 31.

The spelling of 61505005531 in words is "sixty-one billion, five hundred five million, five thousand, five hundred thirty-one".