72215690 has 8 divisors (see below), whose sum is σ = 129988260. Its totient is φ = 28886272.

The previous prime is 72215687. The next prime is 72215723. The reversal of 72215690 is 9651227.

It can be written as a sum of positive squares in 2 ways, for example, as 65626201 + 6589489 = 8101^2 + 2567^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×72215690² = 10430211764352200, which contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 3610775 + ... + 3610794.

Almost surely, 2^72215690 is an apocalyptic number.

72215690 is a deficient number, since it is larger than the sum of its proper divisors (57772570).

72215690 is a wasteful number, since it uses less digits than its factorization.

72215690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7221576.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 72215690 is about 8497.9815250446. The cubic root of 72215690 is about 416.4317701794.

The spelling of 72215690 in words is "seventy-two million, two hundred fifteen thousand, six hundred ninety".