55897381 has 2 divisors, whose sum is σ = 55897382. Its totient is φ = 55897380.

The previous prime is 55897333. The next prime is 55897421. The reversal of 55897381 is 18379855.

55897381 = T₆₁₀₃ + T₆₁₀₄ + T₆₁₀₅.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55577025 + 320356 = 7455^2 + 566^2 .

It is a cyclic number.

It is not a de Polignac number, because 55897381 - 2⁷ = 55897253 is a prime.

It is a super-2 number, since 2×55897381² = 6249034405318322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55817381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27948690 + 27948691.

It is an arithmetic number, because the mean of its divisors is an integer number (27948691).

Almost surely, 2^55897381 is an apocalyptic number.

55897381 is the 6105-th centered triangular number.

It is an amenable number.

55897381 is a deficient number, since it is larger than the sum of its proper divisors (1).

55897381 is an equidigital number, since it uses as much as digits as its factorization.

55897381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 302400, while the sum is 46.

The square root of 55897381 is about 7476.4551092078. The cubic root of 55897381 is about 382.3523995133.

The spelling of 55897381 in words is "fifty-five million, eight hundred ninety-seven thousand, three hundred eighty-one".