77985497 has 4 divisors (see below), whose sum is σ = 78011136. Its totient is φ = 77959860.

The previous prime is 77985473. The next prime is 77985499. The reversal of 77985497 is 79458977.

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, and also an emirpimes, since its reverse is a distinct semiprime: 79458977 = 13 ⋅6112229.

It is a cyclic number.

It is not a de Polignac number, because 77985497 - 2⁸ = 77985241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77985499) 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, 7529 + ... + 14582.

It is an arithmetic number, because the mean of its divisors is an integer number (19502784).

Almost surely, 2^77985497 is an apocalyptic number.

It is an amenable number.

77985497 is a deficient number, since it is larger than the sum of its proper divisors (25639).

77985497 is a wasteful number, since it uses less digits than its factorization.

77985497 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25638.

The product of its digits is 4445280, while the sum is 56.

The square root of 77985497 is about 8830.9397574664. The cubic root of 77985497 is about 427.2393851741.

The spelling of 77985497 in words is "seventy-seven million, nine hundred eighty-five thousand, four hundred ninety-seven".