78247253 has 4 divisors (see below), whose sum is σ = 89425440. Its totient is φ = 67069068.

The previous prime is 78247241. The next prime is 78247259. The reversal of 78247253 is 35274287.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 35274287 = 61 ⋅578267.

It is a cyclic number.

It is not a de Polignac number, because 78247253 - 2²⁰ = 77198677 is a prime.

It is a super-2 number, since 2×78247253² = 12245265204092018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78247259) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5589083 + ... + 5589096.

It is an arithmetic number, because the mean of its divisors is an integer number (22356360).

Almost surely, 2^78247253 is an apocalyptic number.

It is an amenable number.

78247253 is a deficient number, since it is larger than the sum of its proper divisors (11178187).

78247253 is a wasteful number, since it uses less digits than its factorization.

78247253 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11178186.

The product of its digits is 94080, while the sum is 38.

The square root of 78247253 is about 8845.7477354942. The cubic root of 78247253 is about 427.7168567930.

The spelling of 78247253 in words is "seventy-eight million, two hundred forty-seven thousand, two hundred fifty-three".