213777971 has 8 divisors (see below), whose sum is σ = 239515824. Its totient is φ = 189090720.

The previous prime is 213777959. The next prime is 213777973. The reversal of 213777971 is 179777312.

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

It is a de Polignac number, because none of the positive numbers 2^k-213777971 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213777973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 262220 + ... + 263033.

It is an arithmetic number, because the mean of its divisors is an integer number (29939478).

Almost surely, 2^213777971 is an apocalyptic number.

213777971 is a deficient number, since it is larger than the sum of its proper divisors (25737853).

213777971 is a wasteful number, since it uses less digits than its factorization.

213777971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 525301.

The product of its digits is 129654, while the sum is 44.

The square root of 213777971 is about 14621.1480739373. The cubic root of 213777971 is about 597.9354700822.

It can be divided in two parts, 2137 and 77971, that added together give a palindrome (80108).

The spelling of 213777971 in words is "two hundred thirteen million, seven hundred seventy-seven thousand, nine hundred seventy-one".