78288971 has 2 divisors, whose sum is σ = 78288972. Its totient is φ = 78288970.

The previous prime is 78288943. The next prime is 78288979. The reversal of 78288971 is 17988287.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78288971 - 2¹⁴ = 78272587 is a prime.

It is a super-2 number, since 2×78288971² = 12258325960477682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78288979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39144485 + 39144486.

It is an arithmetic number, because the mean of its divisors is an integer number (39144486).

Almost surely, 2^78288971 is an apocalyptic number.

78288971 is a deficient number, since it is larger than the sum of its proper divisors (1).

78288971 is an equidigital number, since it uses as much as digits as its factorization.

78288971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 451584, while the sum is 50.

The square root of 78288971 is about 8848.1055034397. The cubic root of 78288971 is about 427.7928565714.

The spelling of 78288971 in words is "seventy-eight million, two hundred eighty-eight thousand, nine hundred seventy-one".