55021561657 has 16 divisors (see below), whose sum is σ = 55964413440. Its totient is φ = 54087590592.

The previous prime is 55021561627. The next prime is 55021561687. The reversal of 55021561657 is 75616512055.

It is an interprime number because it is at equal distance from previous prime (55021561627) and next prime (55021561687).

It is a cyclic number.

It is not a de Polignac number, because 55021561657 - 2¹¹ = 55021559609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55021561627) 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, 13486944 + ... + 13491022.

It is an arithmetic number, because the mean of its divisors is an integer number (3497775840).

Almost surely, 2^55021561657 is an apocalyptic number.

It is an amenable number.

55021561657 is a deficient number, since it is larger than the sum of its proper divisors (942851783).

55021561657 is a wasteful number, since it uses less digits than its factorization.

55021561657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5112.

The product of its (nonzero) digits is 315000, while the sum is 43.

The spelling of 55021561657 in words is "fifty-five billion, twenty-one million, five hundred sixty-one thousand, six hundred fifty-seven".