61009788491 has 2 divisors, whose sum is σ = 61009788492. Its totient is φ = 61009788490.

The previous prime is 61009788401. The next prime is 61009788527. The reversal of 61009788491 is 19488790016.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61009788491 is a prime.

It is not a weakly prime, because it can be changed into another prime (61009788401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30504894245 + 30504894246.

It is an arithmetic number, because the mean of its divisors is an integer number (30504894246).

Almost surely, 2^61009788491 is an apocalyptic number.

61009788491 is a deficient number, since it is larger than the sum of its proper divisors (1).

61009788491 is an equidigital number, since it uses as much as digits as its factorization.

61009788491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 870912, while the sum is 53.

The spelling of 61009788491 in words is "sixty-one billion, nine million, seven hundred eighty-eight thousand, four hundred ninety-one".