213972491 has 8 divisors (see below), whose sum is σ = 215904864. Its totient is φ = 212045760.

The previous prime is 213972463. The next prime is 213972497. The reversal of 213972491 is 194279312.

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 213972491 - 2¹⁴ = 213956107 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213972497) 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, 115946 + ... + 117776.

It is an arithmetic number, because the mean of its divisors is an integer number (26988108).

Almost surely, 2^213972491 is an apocalyptic number.

213972491 is a deficient number, since it is larger than the sum of its proper divisors (1932373).

213972491 is a wasteful number, since it uses less digits than its factorization.

213972491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2821.

The product of its digits is 27216, while the sum is 38.

The square root of 213972491 is about 14627.7985698464. The cubic root of 213972491 is about 598.1167721240.

The spelling of 213972491 in words is "two hundred thirteen million, nine hundred seventy-two thousand, four hundred ninety-one".