6139981 has 4 divisors (see below), whose sum is σ = 6197472. Its totient is φ = 6082492.

The previous prime is 6139979. The next prime is 6139993. The reversal of 6139981 is 1899316.

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 a cyclic number.

It is not a de Polignac number, because 6139981 - 2¹ = 6139979 is a prime.

It is a super-2 number, since 2×6139981² = 75398733360722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6139981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6139901) 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, 28585 + ... + 28798.

It is an arithmetic number, because the mean of its divisors is an integer number (1549368).

Almost surely, 2^6139981 is an apocalyptic number.

It is an amenable number.

6139981 is a deficient number, since it is larger than the sum of its proper divisors (57491).

6139981 is a wasteful number, since it uses less digits than its factorization.

6139981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57490.

The product of its digits is 11664, while the sum is 37.

The square root of 6139981 is about 2477.8985047818. The cubic root of 6139981 is about 183.1143342769.

The spelling of 6139981 in words is "six million, one hundred thirty-nine thousand, nine hundred eighty-one".