68545981 has 4 divisors (see below), whose sum is σ = 78338272. Its totient is φ = 58753692.

The previous prime is 68545933. The next prime is 68545993. The reversal of 68545981 is 18954586.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 68545981 - 2¹⁷ = 68414909 is a prime.

It is a super-2 number, since 2×68545981² = 9397103022504722, 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 (68545181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4896135 + ... + 4896148.

It is an arithmetic number, because the mean of its divisors is an integer number (19584568).

Almost surely, 2^68545981 is an apocalyptic number.

It is an amenable number.

68545981 is a deficient number, since it is larger than the sum of its proper divisors (9792291).

68545981 is an equidigital number, since it uses as much as digits as its factorization.

68545981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9792290.

The product of its digits is 345600, while the sum is 46.

The square root of 68545981 is about 8279.2500264215. The cubic root of 68545981 is about 409.2550044435.

The spelling of 68545981 in words is "sixty-eight million, five hundred forty-five thousand, nine hundred eighty-one".