78243137 has 4 divisors (see below), whose sum is σ = 89420736. Its totient is φ = 67065540.

The previous prime is 78243133. The next prime is 78243149. The reversal of 78243137 is 73134287.

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.

It is a cyclic number.

It is not a de Polignac number, because 78243137 - 2² = 78243133 is a prime.

It is a super-2 number, since 2×78243137² = 12243976975201538, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78243097 and 78243106.

It is not an unprimeable number, because it can be changed into a prime (78243133) 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, 5588789 + ... + 5588802.

It is an arithmetic number, because the mean of its divisors is an integer number (22355184).

Almost surely, 2^78243137 is an apocalyptic number.

It is an amenable number.

78243137 is a deficient number, since it is larger than the sum of its proper divisors (11177599).

78243137 is a wasteful number, since it uses less digits than its factorization.

78243137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11177598.

The product of its digits is 28224, while the sum is 35.

The square root of 78243137 is about 8845.5150782755. The cubic root of 78243137 is about 427.7093570049.

The spelling of 78243137 in words is "seventy-eight million, two hundred forty-three thousand, one hundred thirty-seven".