68993690 has 16 divisors (see below), whose sum is σ = 125585640. Its totient is φ = 27287040.

The previous prime is 68993689. The next prime is 68993741. The reversal of 68993690 is 9639986.

It can be written as a sum of positive squares in 4 ways, for example, as 28912129 + 40081561 = 5377^2 + 6331^2 .

It is a super-2 number, since 2×68993690² = 9520258519632200, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37871 + ... + 39650.

Almost surely, 2^68993690 is an apocalyptic number.

68993690 is a deficient number, since it is larger than the sum of its proper divisors (56591950).

68993690 is a wasteful number, since it uses less digits than its factorization.

68993690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77617.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 68993690 is about 8306.2440368677. The cubic root of 68993690 is about 410.1440897480.

The spelling of 68993690 in words is "sixty-eight million, nine hundred ninety-three thousand, six hundred ninety".