55731997 has 16 divisors (see below), whose sum is σ = 62193600. Its totient is φ = 49714560.

The previous prime is 55731983. The next prime is 55732003. The reversal of 55731997 is 79913755.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 55731997 - 2⁷ = 55731869 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 (55731917) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21358 + ... + 23824.

It is an arithmetic number, because the mean of its divisors is an integer number (3887100).

Almost surely, 2^55731997 is an apocalyptic number.

It is an amenable number.

55731997 is a deficient number, since it is larger than the sum of its proper divisors (6461603).

55731997 is a wasteful number, since it uses less digits than its factorization.

55731997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2556.

The product of its digits is 297675, while the sum is 46.

The square root of 55731997 is about 7465.3865941423. The cubic root of 55731997 is about 381.9749373650.

The spelling of 55731997 in words is "fifty-five million, seven hundred thirty-one thousand, nine hundred ninety-seven".