64611921693 has 8 divisors (see below), whose sum is σ = 93980977056. Its totient is φ = 39158740400.

The previous prime is 64611921679. The next prime is 64611921727. The reversal of 64611921693 is 39612911646.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 64611921693 - 2⁶ = 64611921629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64611921623) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 978968478 + ... + 978968543.

It is an arithmetic number, because the mean of its divisors is an integer number (11747622132).

Almost surely, 2^64611921693 is an apocalyptic number.

It is an amenable number.

64611921693 is a deficient number, since it is larger than the sum of its proper divisors (29369055363).

64611921693 is a wasteful number, since it uses less digits than its factorization.

64611921693 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1957937035.

The product of its digits is 419904, while the sum is 48.

The spelling of 64611921693 in words is "sixty-four billion, six hundred eleven million, nine hundred twenty-one thousand, six hundred ninety-three".