7249981 has 2 divisors, whose sum is σ = 7249982. Its totient is φ = 7249980.

The previous prime is 7249961. The next prime is 7249997. The reversal of 7249981 is 1899427.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4972900 + 2277081 = 2230^2 + 1509^2 .

It is a cyclic number.

It is not a de Polignac number, because 7249981 - 2¹⁵ = 7217213 is a prime.

It is a super-2 number, since 2×7249981² = 105124449000722, which contains 22 as substring.

7249981 is a lucky number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7249901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3624990 + 3624991.

It is an arithmetic number, because the mean of its divisors is an integer number (3624991).

Almost surely, 2^7249981 is an apocalyptic number.

It is an amenable number.

7249981 is a deficient number, since it is larger than the sum of its proper divisors (1).

7249981 is an equidigital number, since it uses as much as digits as its factorization.

7249981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 40.

The square root of 7249981 is about 2692.5788753535. The cubic root of 7249981 is about 193.5436629585.

The spelling of 7249981 in words is "seven million, two hundred forty-nine thousand, nine hundred eighty-one".