55780397 has 2 divisors, whose sum is σ = 55780398. Its totient is φ = 55780396.

The previous prime is 55780391. The next prime is 55780411. The reversal of 55780397 is 79308755.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 54922921 + 857476 = 7411^2 + 926^2 .

It is a cyclic number.

It is not a de Polignac number, because 55780397 - 2¹⁶ = 55714861 is a prime.

It is a super-2 number, since 2×55780397² = 6222905378955218, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (55780391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27890198 + 27890199.

It is an arithmetic number, because the mean of its divisors is an integer number (27890199).

Almost surely, 2^55780397 is an apocalyptic number.

It is an amenable number.

55780397 is a deficient number, since it is larger than the sum of its proper divisors (1).

55780397 is an equidigital number, since it uses as much as digits as its factorization.

55780397 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 264600, while the sum is 44.

The square root of 55780397 is about 7468.6275178241. The cubic root of 55780397 is about 382.0854797150.

The spelling of 55780397 in words is "fifty-five million, seven hundred eighty thousand, three hundred ninety-seven".