55703721 has 4 divisors (see below), whose sum is σ = 74271632. Its totient is φ = 37135812.

The previous prime is 55703719. The next prime is 55703743. The reversal of 55703721 is 12730755.

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.

It is not a de Polignac number, because 55703721 - 2¹ = 55703719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55703761) 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, 9283951 + ... + 9283956.

It is an arithmetic number, because the mean of its divisors is an integer number (18567908).

Almost surely, 2^55703721 is an apocalyptic number.

It is an amenable number.

55703721 is a deficient number, since it is larger than the sum of its proper divisors (18567911).

55703721 is a wasteful number, since it uses less digits than its factorization.

55703721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18567910.

The product of its (nonzero) digits is 7350, while the sum is 30.

The square root of 55703721 is about 7463.4925470586. The cubic root of 55703721 is about 381.9103272606.

The spelling of 55703721 in words is "fifty-five million, seven hundred three thousand, seven hundred twenty-one".