215956 has 12 divisors (see below), whose sum is σ = 407092. Its totient is φ = 99648.

The previous prime is 215953. The next prime is 215959. The reversal of 215956 is 659512.

215956 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (215953) and next prime (215959).

It can be written as a sum of positive squares in 2 ways, for example, as 13456 + 202500 = 116^2 + 450^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215953) 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, 2025 + ... + 2128.

2²¹⁵⁹⁵⁶ is an apocalyptic number.

215956 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

215956 is a deficient number, since it is larger than the sum of its proper divisors (191136).

215956 is a wasteful number, since it uses less digits than its factorization.

215956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4170 (or 4168 counting only the distinct ones).

The product of its digits is 2700, while the sum is 28.

The square root of 215956 is about 464.7106626709. The cubic root of 215956 is about 59.9959256493.

Subtracting 215956 from its reverse (659512), we obtain a square (443556 = 666²).

The spelling of 215956 in words is "two hundred fifteen thousand, nine hundred fifty-six".