66801431 has 2 divisors, whose sum is σ = 66801432. Its totient is φ = 66801430.

The previous prime is 66801421. The next prime is 66801439. The reversal of 66801431 is 13410866.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66801431 is a prime.

It is a super-2 number, since 2×66801431² = 8924862367295522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 66801394 and 66801403.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66801439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33400715 + 33400716.

It is an arithmetic number, because the mean of its divisors is an integer number (33400716).

Almost surely, 2^66801431 is an apocalyptic number.

66801431 is a deficient number, since it is larger than the sum of its proper divisors (1).

66801431 is an equidigital number, since it uses as much as digits as its factorization.

66801431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 29.

The square root of 66801431 is about 8173.2142392085. The cubic root of 66801431 is about 405.7531704413.

The spelling of 66801431 in words is "sixty-six million, eight hundred one thousand, four hundred thirty-one".