421877681 has 2 divisors, whose sum is σ = 421877682. Its totient is φ = 421877680.

The previous prime is 421877657. The next prime is 421877689. The reversal of 421877681 is 186778124.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 400800400 + 21077281 = 20020^2 + 4591^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-421877681 is a prime.

It is a super-2 number, since 2×421877681² = 355961555451875522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (421877689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210938840 + 210938841.

It is an arithmetic number, because the mean of its divisors is an integer number (210938841).

Almost surely, 2^421877681 is an apocalyptic number.

It is an amenable number.

421877681 is a deficient number, since it is larger than the sum of its proper divisors (1).

421877681 is an equidigital number, since it uses as much as digits as its factorization.

421877681 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 150528, while the sum is 44.

The square root of 421877681 is about 20539.6611705257. The cubic root of 421877681 is about 750.0015887374.

The spelling of 421877681 in words is "four hundred twenty-one million, eight hundred seventy-seven thousand, six hundred eighty-one".