98217721 has 16 divisors (see below), whose sum is σ = 122069376. Its totient is φ = 77089536.

The previous prime is 98217689. The next prime is 98217731. The reversal of 98217721 is 12771289.

It is a cyclic number.

It is not a de Polignac number, because 98217721 - 2⁵ = 98217689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (98217731) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6751 + ... + 15556.

It is an arithmetic number, because the mean of its divisors is an integer number (7629336).

Almost surely, 2^98217721 is an apocalyptic number.

It is an amenable number.

98217721 is a deficient number, since it is larger than the sum of its proper divisors (23851655).

98217721 is a wasteful number, since it uses less digits than its factorization.

98217721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22368.

The product of its digits is 14112, while the sum is 37.

The square root of 98217721 is about 9910.4854068809. The cubic root of 98217721 is about 461.3848014380.

The spelling of 98217721 in words is "ninety-eight million, two hundred seventeen thousand, seven hundred twenty-one".