55773121 has 4 divisors (see below), whose sum is σ = 55788544. Its totient is φ = 55757700.

The previous prime is 55773083. The next prime is 55773167. The reversal of 55773121 is 12137755.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 55773121 - 2¹¹ = 55771073 is a prime.

It is a super-2 number, since 2×55773121² = 6221282052161282, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55753121) 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, 976 + ... + 10606.

It is an arithmetic number, because the mean of its divisors is an integer number (13947136).

Almost surely, 2^55773121 is an apocalyptic number.

It is an amenable number.

55773121 is a deficient number, since it is larger than the sum of its proper divisors (15423).

55773121 is an equidigital number, since it uses as much as digits as its factorization.

55773121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15422.

The product of its digits is 7350, while the sum is 31.

The square root of 55773121 is about 7468.1403977162. The cubic root of 55773121 is about 382.0688659045.

The spelling of 55773121 in words is "fifty-five million, seven hundred seventy-three thousand, one hundred twenty-one".