61838391 has 4 divisors (see below), whose sum is σ = 82451192. Its totient is φ = 41225592.

The previous prime is 61838383. The next prime is 61838393. The reversal of 61838391 is 19383816.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 61838391 - 2³ = 61838383 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 (61838393) 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, 10306396 + ... + 10306401.

It is an arithmetic number, because the mean of its divisors is an integer number (20612798).

Almost surely, 2^61838391 is an apocalyptic number.

61838391 is a deficient number, since it is larger than the sum of its proper divisors (20612801).

61838391 is a wasteful number, since it uses less digits than its factorization.

61838391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20612800.

The product of its digits is 31104, while the sum is 39.

The square root of 61838391 is about 7863.7389961773. The cubic root of 61838391 is about 395.4449741591. Note that the first 3 decimals are identical.

The spelling of 61838391 in words is "sixty-one million, eight hundred thirty-eight thousand, three hundred ninety-one".