77478421 has 8 divisors (see below), whose sum is σ = 82373760. Its totient is φ = 72710352.

The previous prime is 77478391. The next prime is 77478433. The reversal of 77478421 is 12487477.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77478421 - 2⁷ = 77478293 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77478221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30561 + ... + 32998.

It is an arithmetic number, because the mean of its divisors is an integer number (10296720).

Almost surely, 2^77478421 is an apocalyptic number.

It is an amenable number.

77478421 is a deficient number, since it is larger than the sum of its proper divisors (4895339).

77478421 is a wasteful number, since it uses less digits than its factorization.

77478421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63635.

The product of its digits is 87808, while the sum is 40.

The square root of 77478421 is about 8802.1827406615. The cubic root of 77478421 is about 426.3113746214.

The spelling of 77478421 in words is "seventy-seven million, four hundred seventy-eight thousand, four hundred twenty-one".