213378777 has 12 divisors (see below), whose sum is σ = 309780900. Its totient is φ = 141529248.

The previous prime is 213378773. The next prime is 213378791. The reversal of 213378777 is 777873312.

It can be written as a sum of positive squares in 2 ways, for example, as 183304521 + 30074256 = 13539^2 + 5484^2 .

It is not a de Polignac number, because 213378777 - 2² = 213378773 is a prime.

It is not an unprimeable number, because it can be changed into a prime (213378773) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 58402 + ... + 61947.

It is an arithmetic number, because the mean of its divisors is an integer number (25815075).

Almost surely, 2^213378777 is an apocalyptic number.

It is an amenable number.

213378777 is a deficient number, since it is larger than the sum of its proper divisors (96402123).

213378777 is a wasteful number, since it uses less digits than its factorization.

213378777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120552 (or 120549 counting only the distinct ones).

The product of its digits is 345744, while the sum is 45.

The square root of 213378777 is about 14607.4904415509. The cubic root of 213378777 is about 597.5630572503.

The spelling of 213378777 in words is "two hundred thirteen million, three hundred seventy-eight thousand, seven hundred seventy-seven".