917221427 has 8 divisors (see below), whose sum is σ = 927835776. Its totient is φ = 906630912.

The previous prime is 917221423. The next prime is 917221469. The reversal of 917221427 is 724122719.

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

It is a cyclic number.

It is not a de Polignac number, because 917221427 - 2² = 917221423 is a prime.

It is a super-2 number, since 2×917221427² = 1682590292295832658, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (917221423) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 78233 + ... + 89189.

It is an arithmetic number, because the mean of its divisors is an integer number (115979472).

Almost surely, 2^917221427 is an apocalyptic number.

917221427 is a gapful number since it is divisible by the number (97) formed by its first and last digit.

917221427 is a deficient number, since it is larger than the sum of its proper divisors (10614349).

917221427 is a wasteful number, since it uses less digits than its factorization.

917221427 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11917.

The product of its digits is 14112, while the sum is 35.

The square root of 917221427 is about 30285.6637206451. The cubic root of 917221427 is about 971.6087051242.

The spelling of 917221427 in words is "nine hundred seventeen million, two hundred twenty-one thousand, four hundred twenty-seven".