68644381 has 16 divisors (see below), whose sum is σ = 76495104. Its totient is φ = 61199424.

The previous prime is 68644369. The next prime is 68644399. The reversal of 68644381 is 18344686.

It is a de Polignac number, because none of the positive numbers 2^k-68644381 is a prime.

It is a super-2 number, since 2×68644381² = 9424102085746322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68642381) 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, 45420 + ... + 46906.

It is an arithmetic number, because the mean of its divisors is an integer number (4780944).

Almost surely, 2^68644381 is an apocalyptic number.

It is an amenable number.

68644381 is a deficient number, since it is larger than the sum of its proper divisors (7850723).

68644381 is a wasteful number, since it uses less digits than its factorization.

68644381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1620.

The product of its digits is 110592, while the sum is 40.

The square root of 68644381 is about 8285.1904625060. The cubic root of 68644381 is about 409.4507437961.

The spelling of 68644381 in words is "sixty-eight million, six hundred forty-four thousand, three hundred eighty-one".