78152489 has 2 divisors, whose sum is σ = 78152490. Its totient is φ = 78152488.

The previous prime is 78152483. The next prime is 78152507. The reversal of 78152489 is 98425187.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 78145600 + 6889 = 8840^2 + 83^2 .

It is a cyclic number.

It is not a de Polignac number, because 78152489 - 2¹² = 78148393 is a prime.

It is a super-2 number, since 2×78152489² = 12215623073790242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (78152483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39076244 + 39076245.

It is an arithmetic number, because the mean of its divisors is an integer number (39076245).

Almost surely, 2^78152489 is an apocalyptic number.

It is an amenable number.

78152489 is a deficient number, since it is larger than the sum of its proper divisors (1).

78152489 is an equidigital number, since it uses as much as digits as its factorization.

78152489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 161280, while the sum is 44.

The square root of 78152489 is about 8840.3896407342. The cubic root of 78152489 is about 427.5441200204.

The spelling of 78152489 in words is "seventy-eight million, one hundred fifty-two thousand, four hundred eighty-nine".