77428947 has 8 divisors (see below), whose sum is σ = 104931280. Its totient is φ = 50772960.

The previous prime is 77428943. The next prime is 77428969. The reversal of 77428947 is 74982477.

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

It is not a de Polignac number, because 77428947 - 2² = 77428943 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77428896 and 77428905.

It is not an unprimeable number, because it can be changed into a prime (77428943) 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, 211372 + ... + 211737.

It is an arithmetic number, because the mean of its divisors is an integer number (13116410).

Almost surely, 2^77428947 is an apocalyptic number.

77428947 is a deficient number, since it is larger than the sum of its proper divisors (27502333).

77428947 is a wasteful number, since it uses less digits than its factorization.

77428947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 423173.

The product of its digits is 790272, while the sum is 48.

The square root of 77428947 is about 8799.3719662258. The cubic root of 77428947 is about 426.2206146413.

The spelling of 77428947 in words is "seventy-seven million, four hundred twenty-eight thousand, nine hundred forty-seven".