61840939649 has 4 divisors (see below), whose sum is σ = 62418892464. Its totient is φ = 61262986836.

The previous prime is 61840939613. The next prime is 61840939673. The reversal of 61840939649 is 94693904816.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 61840939649 - 2⁸ = 61840939393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61840939949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 288976247 + ... + 288976460.

It is an arithmetic number, because the mean of its divisors is an integer number (15604723116).

Almost surely, 2^61840939649 is an apocalyptic number.

It is an amenable number.

61840939649 is a deficient number, since it is larger than the sum of its proper divisors (577952815).

61840939649 is a wasteful number, since it uses less digits than its factorization.

61840939649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577952814.

The product of its (nonzero) digits is 10077696, while the sum is 59.

The spelling of 61840939649 in words is "sixty-one billion, eight hundred forty million, nine hundred thirty-nine thousand, six hundred forty-nine".