72218775 has 24 divisors (see below), whose sum is σ = 119655040. Its totient is φ = 38435040.

The previous prime is 72218767. The next prime is 72218779. The reversal of 72218775 is 57781227.

It is not a de Polignac number, because 72218775 - 2³ = 72218767 is a prime.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72218779) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 54774 + ... + 56076.

Almost surely, 2^72218775 is an apocalyptic number.

72218775 is a gapful number since it is divisible by the number (75) formed by its first and last digit.

72218775 is a deficient number, since it is larger than the sum of its proper divisors (47436265).

72218775 is a wasteful number, since it uses less digits than its factorization.

72218775 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2055 (or 2050 counting only the distinct ones).

The product of its digits is 54880, while the sum is 39.

The square root of 72218775 is about 8498.1630367980. The cubic root of 72218775 is about 416.4376999790.

The spelling of 72218775 in words is "seventy-two million, two hundred eighteen thousand, seven hundred seventy-five".