55540565391 has 16 divisors (see below), whose sum is σ = 74809304064. Its totient is φ = 36651230304.

The previous prime is 55540565317. The next prime is 55540565467. The reversal of 55540565391 is 19356504555.

It is not a de Polignac number, because 55540565391 - 2¹⁵ = 55540532623 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 55540565391.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55540565291) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100311 + ... + 348056.

It is an arithmetic number, because the mean of its divisors is an integer number (4675581504).

Almost surely, 2^55540565391 is an apocalyptic number.

55540565391 is a deficient number, since it is larger than the sum of its proper divisors (19268738673).

55540565391 is a wasteful number, since it uses less digits than its factorization.

55540565391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448790.

The product of its (nonzero) digits is 2025000, while the sum is 48.

The spelling of 55540565391 in words is "fifty-five billion, five hundred forty million, five hundred sixty-five thousand, three hundred ninety-one".