77871897 has 6 divisors (see below), whose sum is σ = 112481642. Its totient is φ = 51914592.

The previous prime is 77871887. The next prime is 77871901. The reversal of 77871897 is 79817877.

It can be written as a sum of positive squares in only one way, i.e., 56610576 + 21261321 = 7524^2 + 4611^2 .

It is not a de Polignac number, because 77871897 - 2⁴ = 77871881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77871817) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4326208 + ... + 4326225.

Almost surely, 2^77871897 is an apocalyptic number.

It is an amenable number.

77871897 is a deficient number, since it is larger than the sum of its proper divisors (34609745).

77871897 is a wasteful number, since it uses less digits than its factorization.

77871897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8652439 (or 8652436 counting only the distinct ones).

The product of its digits is 1382976, while the sum is 54.

The square root of 77871897 is about 8824.5054818953. The cubic root of 77871897 is about 427.0318338495.

The spelling of 77871897 in words is "seventy-seven million, eight hundred seventy-one thousand, eight hundred ninety-seven".