77280993 has 8 divisors (see below), whose sum is σ = 114490400. Its totient is φ = 51520644.

The previous prime is 77280991. The next prime is 77281007. The reversal of 77280993 is 39908277.

It is not a de Polignac number, because 77280993 - 2¹ = 77280991 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77280991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1431103 + ... + 1431156.

It is an arithmetic number, because the mean of its divisors is an integer number (14311300).

Almost surely, 2^77280993 is an apocalyptic number.

It is an amenable number.

77280993 is a deficient number, since it is larger than the sum of its proper divisors (37209407).

77280993 is a wasteful number, since it uses less digits than its factorization.

77280993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2862268 (or 2862262 counting only the distinct ones).

The product of its (nonzero) digits is 190512, while the sum is 45.

The square root of 77280993 is about 8790.9608689835. The cubic root of 77280993 is about 425.9489623442.

The spelling of 77280993 in words is "seventy-seven million, two hundred eighty thousand, nine hundred ninety-three".