66631969 has 8 divisors (see below), whose sum is σ = 67796000. Its totient is φ = 65473056.

The previous prime is 66631963. The next prime is 66631979. The reversal of 66631969 is 96913666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66631969 - 2²¹ = 64534817 is a prime.

It is a super-2 number, since 2×66631969² = 8879638585633922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66631963) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32437 + ... + 34429.

It is an arithmetic number, because the mean of its divisors is an integer number (8474500).

Almost surely, 2^66631969 is an apocalyptic number.

It is an amenable number.

66631969 is a deficient number, since it is larger than the sum of its proper divisors (1164031).

66631969 is a wasteful number, since it uses less digits than its factorization.

66631969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2559.

The product of its digits is 314928, while the sum is 46.

The square root of 66631969 is about 8162.8407432707. The cubic root of 66631969 is about 405.4097747580.

It can be divided in two parts, 66631 and 969, that added together give a square (67600 = 260²).

The spelling of 66631969 in words is "sixty-six million, six hundred thirty-one thousand, nine hundred sixty-nine".