55780409 has 4 divisors (see below), whose sum is σ = 58716240. Its totient is φ = 52844580.

The previous prime is 55780397. The next prime is 55780411. The reversal of 55780409 is 90408755.

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 an emirpimes, since its reverse is a distinct semiprime: 90408755 = 5 ⋅18081751.

It is a cyclic number.

It is not a de Polignac number, because 55780409 - 2¹⁶ = 55714873 is a prime.

It is a super-2 number, since 2×55780409² = 6222908056414562, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (55780469) 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, 1467887 + ... + 1467924.

It is an arithmetic number, because the mean of its divisors is an integer number (14679060).

Almost surely, 2^55780409 is an apocalyptic number.

It is an amenable number.

55780409 is a deficient number, since it is larger than the sum of its proper divisors (2935831).

55780409 is a wasteful number, since it uses less digits than its factorization.

55780409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2935830.

The product of its (nonzero) digits is 50400, while the sum is 38.

The square root of 55780409 is about 7468.6283211846. The cubic root of 55780409 is about 382.0855071143.

The spelling of 55780409 in words is "fifty-five million, seven hundred eighty thousand, four hundred nine".