38720421 has 12 divisors (see below), whose sum is σ = 56847180. Its totient is φ = 25390080.

The previous prime is 38720417. The next prime is 38720443. The reversal of 38720421 is 12402783.

It can be written as a sum of positive squares in 2 ways, for example, as 9235521 + 29484900 = 3039^2 + 5430^2 .

It is not a de Polignac number, because 38720421 - 2² = 38720417 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (38720491) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34716 + ... + 35813.

It is an arithmetic number, because the mean of its divisors is an integer number (4737265).

Almost surely, 2^38720421 is an apocalyptic number.

It is an amenable number.

38720421 is a deficient number, since it is larger than the sum of its proper divisors (18126759).

38720421 is a wasteful number, since it uses less digits than its factorization.

38720421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70596 (or 70593 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 38720421 is about 6222.5735029809. The cubic root of 38720421 is about 338.3088484523.

The spelling of 38720421 in words is "thirty-eight million, seven hundred twenty thousand, four hundred twenty-one".