38621581 has 2 divisors, whose sum is σ = 38621582. Its totient is φ = 38621580.

The previous prime is 38621519. The next prime is 38621587. The reversal of 38621581 is 18512683.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29800681 + 8820900 = 5459^2 + 2970^2 .

It is a cyclic number.

It is not a de Polignac number, because 38621581 - 2¹⁵ = 38588813 is a prime.

It is a super-2 number, since 2×38621581² = 2983253037879122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (38621587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19310790 + 19310791.

It is an arithmetic number, because the mean of its divisors is an integer number (19310791).

Almost surely, 2^38621581 is an apocalyptic number.

It is an amenable number.

38621581 is a deficient number, since it is larger than the sum of its proper divisors (1).

38621581 is an equidigital number, since it uses as much as digits as its factorization.

38621581 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 34.

The square root of 38621581 is about 6214.6263765411. The cubic root of 38621581 is about 338.0207408815.

The spelling of 38621581 in words is "thirty-eight million, six hundred twenty-one thousand, five hundred eighty-one".