77016421 has 4 divisors (see below), whose sum is σ = 77076832. Its totient is φ = 76956012.

The previous prime is 77016413. The next prime is 77016449. The reversal of 77016421 is 12461077.

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: 12461077 = 101 ⋅123377.

It is a cyclic number.

It is not a de Polignac number, because 77016421 - 2³ = 77016413 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77016421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77016451) 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, 28251 + ... + 30856.

It is an arithmetic number, because the mean of its divisors is an integer number (19269208).

Almost surely, 2^77016421 is an apocalyptic number.

It is an amenable number.

77016421 is a deficient number, since it is larger than the sum of its proper divisors (60411).

77016421 is a wasteful number, since it uses less digits than its factorization.

77016421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60410.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 77016421 is about 8775.9000108251. The cubic root of 77016421 is about 425.4623268740.

Adding to 77016421 its reverse (12461077), we get a palindrome (89477498).

The spelling of 77016421 in words is "seventy-seven million, sixteen thousand, four hundred twenty-one".