78029257 has 4 divisors (see below), whose sum is σ = 82136080. Its totient is φ = 73922436.

The previous prime is 78029239. The next prime is 78029291. The reversal of 78029257 is 75292087.

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 78029257 - 2¹⁹ = 77504969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78029297) 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, 2053383 + ... + 2053420.

It is an arithmetic number, because the mean of its divisors is an integer number (20534020).

Almost surely, 2^78029257 is an apocalyptic number.

It is an amenable number.

78029257 is a deficient number, since it is larger than the sum of its proper divisors (4106823).

78029257 is a wasteful number, since it uses less digits than its factorization.

78029257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4106822.

The product of its (nonzero) digits is 70560, while the sum is 40.

The square root of 78029257 is about 8833.4170624963. The cubic root of 78029257 is about 427.3192825069.

The spelling of 78029257 in words is "seventy-eight million, twenty-nine thousand, two hundred fifty-seven".