39387421 has 4 divisors (see below), whose sum is σ = 39431200. Its totient is φ = 39343644.

The previous prime is 39387409. The next prime is 39387433. The reversal of 39387421 is 12478393.

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.

It is an interprime number because it is at equal distance from previous prime (39387409) and next prime (39387433).

It is a cyclic number.

It is not a de Polignac number, because 39387421 - 2⁵ = 39387389 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39387221) 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, 20511 + ... + 22348.

It is an arithmetic number, because the mean of its divisors is an integer number (9857800).

Almost surely, 2^39387421 is an apocalyptic number.

It is an amenable number.

39387421 is a deficient number, since it is larger than the sum of its proper divisors (43779).

39387421 is an equidigital number, since it uses as much as digits as its factorization.

39387421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43778.

The product of its digits is 36288, while the sum is 37.

The square root of 39387421 is about 6275.9398499348. The cubic root of 39387421 is about 340.2403750011.

The spelling of 39387421 in words is "thirty-nine million, three hundred eighty-seven thousand, four hundred twenty-one".