78499997 has 2 divisors, whose sum is σ = 78499998. Its totient is φ = 78499996.

The previous prime is 78499991. The next prime is 78500003. The reversal of 78499997 is 79999487.

It is a balanced prime because it is at equal distance from previous prime (78499991) and next prime (78500003).

It can be written as a sum of positive squares in only one way, i.e., 73633561 + 4866436 = 8581^2 + 2206^2 .

It is a cyclic number.

It is not a de Polignac number, because 78499997 - 2⁶ = 78499933 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78499991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39249998 + 39249999.

It is an arithmetic number, because the mean of its divisors is an integer number (39249999).

Almost surely, 2^78499997 is an apocalyptic number.

It is an amenable number.

78499997 is a deficient number, since it is larger than the sum of its proper divisors (1).

78499997 is an equidigital number, since it uses as much as digits as its factorization.

78499997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10287648, while the sum is 62.

The square root of 78499997 is about 8860.0224040349. The cubic root of 78499997 is about 428.1768801178.

The spelling of 78499997 in words is "seventy-eight million, four hundred ninety-nine thousand, nine hundred ninety-seven".