421356657881 has 2 divisors, whose sum is σ = 421356657882. Its totient is φ = 421356657880.

The previous prime is 421356657877. The next prime is 421356657929. The reversal of 421356657881 is 188756653124.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 418706055625 + 2650602256 = 647075^2 + 51484^2 .

It is a cyclic number.

It is not a de Polignac number, because 421356657881 - 2² = 421356657877 is a prime.

It is a super-2 number, since 2×421356657881² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (421356657481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210678328940 + 210678328941.

It is an arithmetic number, because the mean of its divisors is an integer number (210678328941).

Almost surely, 2^421356657881 is an apocalyptic number.

It is an amenable number.

421356657881 is a deficient number, since it is larger than the sum of its proper divisors (1).

421356657881 is an equidigital number, since it uses as much as digits as its factorization.

421356657881 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9676800, while the sum is 56.

The spelling of 421356657881 in words is "four hundred twenty-one billion, three hundred fifty-six million, six hundred fifty-seven thousand, eight hundred eighty-one".