74137781 has 8 divisors (see below), whose sum is σ = 75075000. Its totient is φ = 73206720.

The previous prime is 74137769. The next prime is 74137823. The reversal of 74137781 is 18773147.

It can be written as a sum of positive squares in 4 ways, for example, as 10297681 + 63840100 = 3209^2 + 7990^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 74137781 - 2¹⁰ = 74136757 is a prime.

It is a super-2 number, since 2×74137781² = 10992821143207922, 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 (74137081) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25595 + ... + 28343.

It is an arithmetic number, because the mean of its divisors is an integer number (9384375).

Almost surely, 2^74137781 is an apocalyptic number.

It is an amenable number.

74137781 is a deficient number, since it is larger than the sum of its proper divisors (937219).

74137781 is a wasteful number, since it uses less digits than its factorization.

74137781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3079.

The product of its digits is 32928, while the sum is 38.

The square root of 74137781 is about 8610.3299007645. The cubic root of 74137781 is about 420.0940473443.

The spelling of 74137781 in words is "seventy-four million, one hundred thirty-seven thousand, seven hundred eighty-one".