55197681 has 32 divisors (see below), whose sum is σ = 93907968. Its totient is φ = 28002240.

The previous prime is 55197671. The next prime is 55197697. The reversal of 55197681 is 18679155.

It is not a de Polignac number, because 55197681 - 2⁶ = 55197617 is a prime.

It is a super-2 number, since 2×55197681² = 6093567975555522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55197671) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7155 + ... + 12711.

It is an arithmetic number, because the mean of its divisors is an integer number (2934624).

Almost surely, 2^55197681 is an apocalyptic number.

It is an amenable number.

55197681 is a deficient number, since it is larger than the sum of its proper divisors (38710287).

55197681 is a wasteful number, since it uses less digits than its factorization.

55197681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5621.

The product of its digits is 75600, while the sum is 42.

The square root of 55197681 is about 7429.5141833097. The cubic root of 55197681 is about 380.7503203593.

The spelling of 55197681 in words is "fifty-five million, one hundred ninety-seven thousand, six hundred eighty-one".