7215997 has 4 divisors (see below), whose sum is σ = 7529760. Its totient is φ = 6902236.

The previous prime is 7215979. The next prime is 7216009. The reversal of 7215997 is 7995127.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 7995127 = 7 ⋅1142161.

It is a cyclic number.

It is not a de Polignac number, because 7215997 - 2⁷ = 7215869 is a prime.

It is a super-2 number, since 2×7215997² = 104141225408018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7215697) 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, 156847 + ... + 156892.

It is an arithmetic number, because the mean of its divisors is an integer number (1882440).

Almost surely, 2^7215997 is an apocalyptic number.

It is an amenable number.

7215997 is a deficient number, since it is larger than the sum of its proper divisors (313763).

7215997 is a wasteful number, since it uses less digits than its factorization.

7215997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313762.

The product of its digits is 39690, while the sum is 40.

The square root of 7215997 is about 2686.2607840640. The cubic root of 7215997 is about 193.2407797844.

The spelling of 7215997 in words is "seven million, two hundred fifteen thousand, nine hundred ninety-seven".