66357421 has 16 divisors (see below), whose sum is σ = 73241280. Its totient is φ = 59748480.

The previous prime is 66357407. The next prime is 66357427. The reversal of 66357421 is 12475366.

It is a happy number.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66357421 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 (66357427) 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, 95686 + ... + 96376.

It is an arithmetic number, because the mean of its divisors is an integer number (4577580).

Almost surely, 2^66357421 is an apocalyptic number.

It is an amenable number.

66357421 is a deficient number, since it is larger than the sum of its proper divisors (6883859).

66357421 is a wasteful number, since it uses less digits than its factorization.

66357421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876.

The product of its digits is 30240, while the sum is 34.

The square root of 66357421 is about 8146.0064448784. The cubic root of 66357421 is about 404.8521962311.

The spelling of 66357421 in words is "sixty-six million, three hundred fifty-seven thousand, four hundred twenty-one".