55137981 has 8 divisors (see below), whose sum is σ = 77386720. Its totient is φ = 34823952.

The previous prime is 55137959. The next prime is 55137991. The reversal of 55137981 is 18973155.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 55137981 - 2⁶ = 55137917 is a prime.

It is a super-2 number, since 2×55137981² = 6080393897512722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55137941) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 483610 + ... + 483723.

It is an arithmetic number, because the mean of its divisors is an integer number (9673340).

Almost surely, 2^55137981 is an apocalyptic number.

It is an amenable number.

55137981 is a deficient number, since it is larger than the sum of its proper divisors (22248739).

55137981 is a wasteful number, since it uses less digits than its factorization.

55137981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 967355.

The product of its digits is 37800, while the sum is 39.

The square root of 55137981 is about 7425.4953370129. The cubic root of 55137981 is about 380.6130018247.

The spelling of 55137981 in words is "fifty-five million, one hundred thirty-seven thousand, nine hundred eighty-one".