97887192778 has 4 divisors (see below), whose sum is σ = 146830789170. Its totient is φ = 48943596388.

The previous prime is 97887192773. The next prime is 97887192779. The reversal of 97887192778 is 87729178879.

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

It can be written as a sum of positive squares in only one way, i.e., 80311592449 + 17575600329 = 283393^2 + 132573^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 97887192778.

It is not an unprimeable number, because it can be changed into a prime (97887192773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24471798193 + ... + 24471798196.

Almost surely, 2^97887192778 is an apocalyptic number.

97887192778 is a deficient number, since it is larger than the sum of its proper divisors (48943596392).

97887192778 is a wasteful number, since it uses less digits than its factorization.

97887192778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48943596391.

The product of its digits is 199148544, while the sum is 73.

The spelling of 97887192778 in words is "ninety-seven billion, eight hundred eighty-seven million, one hundred ninety-two thousand, seven hundred seventy-eight".