78249997 has 16 divisors (see below), whose sum is σ = 95679360. Its totient is φ = 62466048.

The previous prime is 78249973. The next prime is 78250001. The reversal of 78249997 is 79994287.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78249997 is a prime.

It is a super-2 number, since 2×78249997² = 12246124061000018, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78249947) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8154 + ... + 14932.

It is an arithmetic number, because the mean of its divisors is an integer number (5979960).

Almost surely, 2^78249997 is an apocalyptic number.

It is an amenable number.

78249997 is a deficient number, since it is larger than the sum of its proper divisors (17429363).

78249997 is a wasteful number, since it uses less digits than its factorization.

78249997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6900.

The product of its digits is 2286144, while the sum is 55.

The square root of 78249997 is about 8845.9028369070. The cubic root of 78249997 is about 427.7218565057.

The spelling of 78249997 in words is "seventy-eight million, two hundred forty-nine thousand, nine hundred ninety-seven".