55270991 has 2 divisors, whose sum is σ = 55270992. Its totient is φ = 55270990.

The previous prime is 55270979. The next prime is 55271077. The reversal of 55270991 is 19907255.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55270991 is a prime.

It is a super-2 number, since 2×55270991² = 6109764892244162, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55270931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27635495 + 27635496.

It is an arithmetic number, because the mean of its divisors is an integer number (27635496).

Almost surely, 2^55270991 is an apocalyptic number.

55270991 is a deficient number, since it is larger than the sum of its proper divisors (1).

55270991 is an equidigital number, since it uses as much as digits as its factorization.

55270991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28350, while the sum is 38.

The square root of 55270991 is about 7434.4462470314. The cubic root of 55270991 is about 380.9188084628.

The spelling of 55270991 in words is "fifty-five million, two hundred seventy thousand, nine hundred ninety-one".