77947145 has 8 divisors (see below), whose sum is σ = 93600456. Its totient is φ = 62315136.

The previous prime is 77947117. The next prime is 77947171. The reversal of 77947145 is 54174977.

It can be written as a sum of positive squares in 4 ways, for example, as 2795584 + 75151561 = 1672^2 + 8669^2 .

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 77947145 - 2²⁶ = 10838281 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77947096 and 77947105.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4319 + ... + 13211.

It is an arithmetic number, because the mean of its divisors is an integer number (11700057).

Almost surely, 2^77947145 is an apocalyptic number.

It is an amenable number.

77947145 is a deficient number, since it is larger than the sum of its proper divisors (15653311).

77947145 is a wasteful number, since it uses less digits than its factorization.

77947145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10651.

The product of its digits is 246960, while the sum is 44.

The square root of 77947145 is about 8828.7680341031. The cubic root of 77947145 is about 427.1693372280.

The spelling of 77947145 in words is "seventy-seven million, nine hundred forty-seven thousand, one hundred forty-five".