7261381621 has 4 divisors (see below), whose sum is σ = 7819949452. Its totient is φ = 6702813792.

The previous prime is 7261381619. The next prime is 7261381637. The reversal of 7261381621 is 1261831627.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2491407396 + 4769974225 = 49914^2 + 69065^2 .

It is a cyclic number.

It is not a de Polignac number, because 7261381621 - 2¹ = 7261381619 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7261381691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 279283896 + ... + 279283921.

It is an arithmetic number, because the mean of its divisors is an integer number (1954987363).

Almost surely, 2^7261381621 is an apocalyptic number.

It is an amenable number.

7261381621 is a deficient number, since it is larger than the sum of its proper divisors (558567831).

7261381621 is a wasteful number, since it uses less digits than its factorization.

7261381621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 558567830.

The product of its digits is 24192, while the sum is 37.

The square root of 7261381621 is about 85213.7407992396. The cubic root of 7261381621 is about 1936.4505919532.

The spelling of 7261381621 in words is "seven billion, two hundred sixty-one million, three hundred eighty-one thousand, six hundred twenty-one".