55621767 has 16 divisors (see below), whose sum is σ = 77143040. Its totient is φ = 35616672.

The previous prime is 55621757. The next prime is 55621777. The reversal of 55621767 is 76712655.

It is an interprime number because it is at equal distance from previous prime (55621757) and next prime (55621777).

It is not a de Polignac number, because 55621767 - 2¹⁰ = 55620743 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55621757) 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, 5598 + ... + 11940.

It is an arithmetic number, because the mean of its divisors is an integer number (4821440).

Almost surely, 2^55621767 is an apocalyptic number.

55621767 is a deficient number, since it is larger than the sum of its proper divisors (21521273).

55621767 is a wasteful number, since it uses less digits than its factorization.

55621767 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6462.

The product of its digits is 88200, while the sum is 39.

The square root of 55621767 is about 7458.0002011263. Note that the first 3 decimals coincide. The cubic root of 55621767 is about 381.7229403707.

The spelling of 55621767 in words is "fifty-five million, six hundred twenty-one thousand, seven hundred sixty-seven".