7212661553 has 4 divisors (see below), whose sum is σ = 7636935780. Its totient is φ = 6788387328.

The previous prime is 7212661537. The next prime is 7212661607. The reversal of 7212661553 is 3551662127.

It is a happy number.

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 2891965729 + 4320695824 = 53777^2 + 65732^2 .

It is a cyclic number.

It is not a de Polignac number, because 7212661553 - 2⁴ = 7212661537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7212661523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 212137088 + ... + 212137121.

It is an arithmetic number, because the mean of its divisors is an integer number (1909233945).

Almost surely, 2^7212661553 is an apocalyptic number.

It is an amenable number.

7212661553 is a deficient number, since it is larger than the sum of its proper divisors (424274227).

7212661553 is a wasteful number, since it uses less digits than its factorization.

7212661553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424274226.

The product of its digits is 75600, while the sum is 38.

The square root of 7212661553 is about 84927.3898868910. The cubic root of 7212661553 is about 1932.1100132999.

The spelling of 7212661553 in words is "seven billion, two hundred twelve million, six hundred sixty-one thousand, five hundred fifty-three".