78120197 has 2 divisors, whose sum is σ = 78120198. Its totient is φ = 78120196.

The previous prime is 78120193. The next prime is 78120233. The reversal of 78120197 is 79102187.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77457601 + 662596 = 8801^2 + 814^2 .

It is a cyclic number.

It is not a de Polignac number, because 78120197 - 2² = 78120193 is a prime.

It is a super-2 number, since 2×78120197² = 12205530358637618, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78120193) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39060098 + 39060099.

It is an arithmetic number, because the mean of its divisors is an integer number (39060099).

Almost surely, 2^78120197 is an apocalyptic number.

It is an amenable number.

78120197 is a deficient number, since it is larger than the sum of its proper divisors (1).

78120197 is an equidigital number, since it uses as much as digits as its factorization.

78120197 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7056, while the sum is 35.

The square root of 78120197 is about 8838.5630619462. The cubic root of 78120197 is about 427.4852259409.

The spelling of 78120197 in words is "seventy-eight million, one hundred twenty thousand, one hundred ninety-seven".