7220781 has 12 divisors (see below), whose sum is σ = 10883808. Its totient is φ = 4604424.

The previous prime is 7220761. The next prime is 7220789. The reversal of 7220781 is 1870227.

It is not a de Polignac number, because 7220781 - 2¹⁰ = 7219757 is a prime.

It is a super-2 number, since 2×7220781² = 104279356499922, which contains 22 as substring.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7220789) 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 11 ways as a sum of consecutive naturals, for example, 17235 + ... + 17648.

It is an arithmetic number, because the mean of its divisors is an integer number (906984).

Almost surely, 2^7220781 is an apocalyptic number.

It is an amenable number.

7220781 is a deficient number, since it is larger than the sum of its proper divisors (3663027).

7220781 is a wasteful number, since it uses less digits than its factorization.

7220781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34912 (or 34909 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 27.

The square root of 7220781 is about 2687.1510936306. The cubic root of 7220781 is about 193.2834747240.

It can be divided in two parts, 7220 and 781, that added together give a triangular number (8001 = T₁₂₆).

The spelling of 7220781 in words is "seven million, two hundred twenty thousand, seven hundred eighty-one".