38724781 has 2 divisors, whose sum is σ = 38724782. Its totient is φ = 38724780.

The previous prime is 38724767. The next prime is 38724841. The reversal of 38724781 is 18742783.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 27562500 + 11162281 = 5250^2 + 3341^2 .

It is a cyclic number.

It is not a de Polignac number, because 38724781 - 2⁹ = 38724269 is a prime.

It is a super-2 number, since 2×38724781² = 2999217326995922, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38724731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19362390 + 19362391.

It is an arithmetic number, because the mean of its divisors is an integer number (19362391).

Almost surely, 2^38724781 is an apocalyptic number.

It is an amenable number.

38724781 is a deficient number, since it is larger than the sum of its proper divisors (1).

38724781 is an equidigital number, since it uses as much as digits as its factorization.

38724781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75264, while the sum is 40.

The square root of 38724781 is about 6222.9238304835. The cubic root of 38724781 is about 338.3215460692.

The spelling of 38724781 in words is "thirty-eight million, seven hundred twenty-four thousand, seven hundred eighty-one".