67649538 has 64 divisors (see below), whose sum is σ = 157708800. Its totient is φ = 19128960.

The previous prime is 67649537. The next prime is 67649539. The reversal of 67649538 is 83594676.

It is an interprime number because it is at equal distance from previous prime (67649537) and next prime (67649539).

It is a super-2 number, since 2×67649538² = 9152919983226888, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (67649537) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 91173 + ... + 91911.

It is an arithmetic number, because the mean of its divisors is an integer number (2464200).

Almost surely, 2^67649538 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 67649538, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78854400).

67649538 is an abundant number, since it is smaller than the sum of its proper divisors (90059262).

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

67649538 is a wasteful number, since it uses less digits than its factorization.

67649538 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847.

The product of its digits is 1088640, while the sum is 48.

The square root of 67649538 is about 8224.9339207072. The cubic root of 67649538 is about 407.4630937507.

The spelling of 67649538 in words is "sixty-seven million, six hundred forty-nine thousand, five hundred thirty-eight".