7218901 has 4 divisors (see below), whose sum is σ = 7267500. Its totient is φ = 7170304.

The previous prime is 7218899. The next prime is 7218907. The reversal of 7218901 is 1098127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1098127 = 181 ⋅6067.

It can be written as a sum of positive squares in 2 ways, for example, as 4626801 + 2592100 = 2151^2 + 1610^2 .

It is a cyclic number.

It is not a de Polignac number, because 7218901 - 2¹ = 7218899 is a prime.

It is a super-2 number, since 2×7218901² = 104225063295602, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 7218901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7218907) 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 3 ways as a sum of consecutive naturals, for example, 24076 + ... + 24373.

It is an arithmetic number, because the mean of its divisors is an integer number (1816875).

Almost surely, 2^7218901 is an apocalyptic number.

It is an amenable number.

7218901 is a deficient number, since it is larger than the sum of its proper divisors (48599).

7218901 is a wasteful number, since it uses less digits than its factorization.

7218901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48598.

The product of its (nonzero) digits is 1008, while the sum is 28.

The square root of 7218901 is about 2686.8012580018. The cubic root of 7218901 is about 193.2666988622.

The spelling of 7218901 in words is "seven million, two hundred eighteen thousand, nine hundred one".