72221457 has 64 divisors (see below), whose sum is σ = 129890304. Its totient is φ = 34544640.

The previous prime is 72221441. The next prime is 72221473. The reversal of 72221457 is 75412227.

It is an interprime number because it is at equal distance from previous prime (72221441) and next prime (72221473).

It is not a de Polignac number, because 72221457 - 2⁴ = 72221441 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72221477) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 207958 + ... + 208304.

It is an arithmetic number, because the mean of its divisors is an integer number (2029536).

Almost surely, 2^72221457 is an apocalyptic number.

72221457 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

It is an amenable number.

72221457 is a deficient number, since it is larger than the sum of its proper divisors (57668847).

72221457 is a wasteful number, since it uses less digits than its factorization.

72221457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438.

The product of its digits is 7840, while the sum is 30.

The square root of 72221457 is about 8498.3208341413. The cubic root of 72221457 is about 416.4428550193.

The spelling of 72221457 in words is "seventy-two million, two hundred twenty-one thousand, four hundred fifty-seven".