7212879540 has 36 divisors (see below), whose sum is σ = 21879068484. Its totient is φ = 1923434496.

The previous prime is 7212879517. The next prime is 7212879559. The reversal of 7212879540 is 459782127.

It is a happy number.

7212879540 is a `hidden beast` number, since 7 + 21 + 2 + 87 + 9 + 540 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 2938073616 + 4274805924 = 54204^2 + 65382^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×7212879540² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20035597 + ... + 20035956.

Almost surely, 2^7212879540 is an apocalyptic number.

It is an amenable number.

7212879540 is an abundant number, since it is smaller than the sum of its proper divisors (14666188944).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7212879540 is a wasteful number, since it uses less digits than its factorization.

7212879540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40071568 (or 40071563 counting only the distinct ones).

The product of its (nonzero) digits is 282240, while the sum is 45.

The square root of 7212879540 is about 84928.6732499690. The cubic root of 7212879540 is about 1932.1294777107.

The spelling of 7212879540 in words is "seven billion, two hundred twelve million, eight hundred seventy-nine thousand, five hundred forty".