97900204778 has 4 divisors (see below), whose sum is σ = 146850307170. Its totient is φ = 48950102388.

The previous prime is 97900204693. The next prime is 97900204781. The reversal of 97900204778 is 87740200979.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87740200979 = 809 ⋅108455131.

It can be written as a sum of positive squares in only one way, i.e., 97695628969 + 204575809 = 312563^2 + 14303^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 24475051193 + ... + 24475051196.

Almost surely, 2^97900204778 is an apocalyptic number.

97900204778 is a deficient number, since it is larger than the sum of its proper divisors (48950102392).

97900204778 is a wasteful number, since it uses less digits than its factorization.

97900204778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48950102391.

The product of its (nonzero) digits is 1778112, while the sum is 53.

The spelling of 97900204778 in words is "ninety-seven billion, nine hundred million, two hundred four thousand, seven hundred seventy-eight".