61353944989 has 4 divisors (see below), whose sum is σ = 61378716924. Its totient is φ = 61329173056.

The previous prime is 61353944963. The next prime is 61353945017. The reversal of 61353944989 is 98944935316.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33492660100 + 27861284889 = 183010^2 + 166917^2 .

It is a cyclic number.

It is not a de Polignac number, because 61353944989 - 2²⁵ = 61320390557 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61353944789) 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, 12382252 + ... + 12387205.

It is an arithmetic number, because the mean of its divisors is an integer number (15344679231).

Almost surely, 2^61353944989 is an apocalyptic number.

It is an amenable number.

61353944989 is a deficient number, since it is larger than the sum of its proper divisors (24771935).

61353944989 is a wasteful number, since it uses less digits than its factorization.

61353944989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24771934.

The product of its digits is 25194240, while the sum is 61.

The spelling of 61353944989 in words is "sixty-one billion, three hundred fifty-three million, nine hundred forty-four thousand, nine hundred eighty-nine".