61978143375 has 24 divisors (see below), whose sum is σ = 111725935152. Its totient is φ = 33055009200.

The previous prime is 61978143373. The next prime is 61978143421. The reversal of 61978143375 is 57334187916.

61978143375 is a `hidden beast` number, since 6 + 197 + 81 + 4 + 3 + 375 = 666.

It is not a de Polignac number, because 61978143375 - 2¹ = 61978143373 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61978143373) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27544717 + ... + 27546966.

It is an arithmetic number, because the mean of its divisors is an integer number (4655247298).

Almost surely, 2^61978143375 is an apocalyptic number.

61978143375 is a deficient number, since it is larger than the sum of its proper divisors (49747791777).

61978143375 is a wasteful number, since it uses less digits than its factorization.

61978143375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55091704 (or 55091691 counting only the distinct ones).

The product of its digits is 3810240, while the sum is 54.

The spelling of 61978143375 in words is "sixty-one billion, nine hundred seventy-eight million, one hundred forty-three thousand, three hundred seventy-five".