61654221887 has 2 divisors, whose sum is σ = 61654221888. Its totient is φ = 61654221886.

The previous prime is 61654221883. The next prime is 61654221901. The reversal of 61654221887 is 78812245616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61654221887 - 2² = 61654221883 is a prime.

It is a super-3 number, since 3×61654221887³ (a number of 33 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61654221883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30827110943 + 30827110944.

It is an arithmetic number, because the mean of its divisors is an integer number (30827110944).

Almost surely, 2^61654221887 is an apocalyptic number.

61654221887 is a deficient number, since it is larger than the sum of its proper divisors (1).

61654221887 is an equidigital number, since it uses as much as digits as its factorization.

61654221887 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1290240, while the sum is 50.

The spelling of 61654221887 in words is "sixty-one billion, six hundred fifty-four million, two hundred twenty-one thousand, eight hundred eighty-seven".