97213644 has 72 divisors (see below), whose sum is σ = 276756480. Its totient is φ = 28504800.

The previous prime is 97213643. The next prime is 97213679. The reversal of 97213644 is 44631279.

97213644 is a `hidden beast` number, since 9 + 7 + 2 + 1 + 3 + 644 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 97213599 and 97213608.

It is not an unprimeable number, because it can be changed into a prime (97213643) 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, 8317 + ... + 16235.

It is an arithmetic number, because the mean of its divisors is an integer number (3843840).

Almost surely, 2^97213644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 97213644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (138378240).

97213644 is an abundant number, since it is smaller than the sum of its proper divisors (179542836).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

97213644 is a wasteful number, since it uses less digits than its factorization.

97213644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7971 (or 7966 counting only the distinct ones).

The product of its digits is 36288, while the sum is 36.

The square root of 97213644 is about 9859.6979669765. The cubic root of 97213644 is about 459.8071718574.

The spelling of 97213644 in words is "ninety-seven million, two hundred thirteen thousand, six hundred forty-four".