77987242 has 4 divisors (see below), whose sum is σ = 116980866. Its totient is φ = 38993620.

The previous prime is 77987237. The next prime is 77987249. The reversal of 77987242 is 24278977.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 54745201 + 23242041 = 7399^2 + 4821^2 .

It is a junction number, because it is equal to n+sod(n) for n = 77987192 and 77987201.

It is not an unprimeable number, because it can be changed into a prime (77987249) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19496809 + ... + 19496812.

Almost surely, 2^77987242 is an apocalyptic number.

77987242 is a deficient number, since it is larger than the sum of its proper divisors (38993624).

77987242 is a wasteful number, since it uses less digits than its factorization.

77987242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38993623.

The product of its digits is 395136, while the sum is 46.

The square root of 77987242 is about 8831.0385572706. The cubic root of 77987242 is about 427.2425717802.

The spelling of 77987242 in words is "seventy-seven million, nine hundred eighty-seven thousand, two hundred forty-two".