38653721 has 4 divisors (see below), whose sum is σ = 38714112. Its totient is φ = 38593332.

The previous prime is 38653717. The next prime is 38653739. The reversal of 38653721 is 12735683.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12735683 = 157 ⋅81119.

It is a cyclic number.

It is not a de Polignac number, because 38653721 - 2² = 38653717 is a prime.

It is a super-2 number, since 2×38653721² = 2988220294291682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38653751) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29225 + ... + 30518.

It is an arithmetic number, because the mean of its divisors is an integer number (9678528).

Almost surely, 2^38653721 is an apocalyptic number.

It is an amenable number.

38653721 is a deficient number, since it is larger than the sum of its proper divisors (60391).

38653721 is an equidigital number, since it uses as much as digits as its factorization.

38653721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60390.

The product of its digits is 30240, while the sum is 35.

The square root of 38653721 is about 6217.2116740545. The cubic root of 38653721 is about 338.1144792710.

The spelling of 38653721 in words is "thirty-eight million, six hundred fifty-three thousand, seven hundred twenty-one".