61881420249 has 24 divisors (see below), whose sum is σ = 97581661632. Its totient is φ = 37476373920.

The previous prime is 61881420247. The next prime is 61881420343. The reversal of 61881420249 is 94202418816.

61881420249 is a `hidden beast` number, since 6 + 188 + 1 + 420 + 2 + 49 = 666.

It is not a de Polignac number, because 61881420249 - 2¹ = 61881420247 is a prime.

It is not an unprimeable number, because it can be changed into a prime (61881420247) 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 in 23 ways as a sum of consecutive naturals, for example, 93294 + ... + 363959.

It is an arithmetic number, because the mean of its divisors is an integer number (4065902568).

Almost surely, 2^61881420249 is an apocalyptic number.

It is an amenable number.

61881420249 is a deficient number, since it is larger than the sum of its proper divisors (35700241383).

61881420249 is a wasteful number, since it uses less digits than its factorization.

61881420249 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458637 (or 458634 counting only the distinct ones).

The product of its (nonzero) digits is 221184, while the sum is 45.

The spelling of 61881420249 in words is "sixty-one billion, eight hundred eighty-one million, four hundred twenty thousand, two hundred forty-nine".