78001771 has 4 divisors (see below), whose sum is σ = 78026112. Its totient is φ = 77977432.

The previous prime is 78001747. The next prime is 78001787. The reversal of 78001771 is 17710087.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17710087 = 37 ⋅478651.

It is a cyclic number.

It is not a de Polignac number, because 78001771 - 2¹³ = 77993579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78001711) 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, 6475 + ... + 14068.

It is an arithmetic number, because the mean of its divisors is an integer number (19506528).

Almost surely, 2^78001771 is an apocalyptic number.

78001771 is a deficient number, since it is larger than the sum of its proper divisors (24341).

78001771 is a wasteful number, since it uses less digits than its factorization.

78001771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24340.

The product of its (nonzero) digits is 2744, while the sum is 31.

The square root of 78001771 is about 8831.8611288901. The cubic root of 78001771 is about 427.2691018541.

The spelling of 78001771 in words is "seventy-eight million, one thousand, seven hundred seventy-one".