66977421 has 32 divisors (see below), whose sum is σ = 104552448. Its totient is φ = 37350720.

The previous prime is 66977411. The next prime is 66977429. The reversal of 66977421 is 12477966.

It is not a de Polignac number, because 66977421 - 2⁷ = 66977293 is a prime.

It is a super-2 number, since 2×66977421² = 8971949847622482, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66977429) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 254536 + ... + 254798.

It is an arithmetic number, because the mean of its divisors is an integer number (3267264).

Almost surely, 2^66977421 is an apocalyptic number.

It is an amenable number.

66977421 is a deficient number, since it is larger than the sum of its proper divisors (37575027).

66977421 is a wasteful number, since it uses less digits than its factorization.

66977421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521.

The product of its digits is 127008, while the sum is 42.

The square root of 66977421 is about 8183.9734237105. The cubic root of 66977421 is about 406.1091801948.

The spelling of 66977421 in words is "sixty-six million, nine hundred seventy-seven thousand, four hundred twenty-one".