78211487 has 2 divisors, whose sum is σ = 78211488. Its totient is φ = 78211486.

The previous prime is 78211459. The next prime is 78211493. The reversal of 78211487 is 78411287.

It is a strong prime.

It is an emirp because it is prime and its reverse (78411287) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 78211487 - 2⁶ = 78211423 is a prime.

It is a super-2 number, since 2×78211487² = 12234073397502338, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78211487.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78211417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39105743 + 39105744.

It is an arithmetic number, because the mean of its divisors is an integer number (39105744).

Almost surely, 2^78211487 is an apocalyptic number.

78211487 is a deficient number, since it is larger than the sum of its proper divisors (1).

78211487 is an equidigital number, since it uses as much as digits as its factorization.

78211487 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 25088, while the sum is 38.

The square root of 78211487 is about 8843.7258550907. The cubic root of 78211487 is about 427.6516785624.

The spelling of 78211487 in words is "seventy-eight million, two hundred eleven thousand, four hundred eighty-seven".