421972987 has 2 divisors, whose sum is σ = 421972988. Its totient is φ = 421972986.

The previous prime is 421972981. The next prime is 421973021. The reversal of 421972987 is 789279124.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 421972987 - 2³ = 421972979 is a prime.

It is a super-2 number, since 2×421972987² = 356122403515404338, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 421972987.

It is not a weakly prime, because it can be changed into another prime (421972981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 210986493 + 210986494.

It is an arithmetic number, because the mean of its divisors is an integer number (210986494).

Almost surely, 2^421972987 is an apocalyptic number.

421972987 is a deficient number, since it is larger than the sum of its proper divisors (1).

421972987 is an equidigital number, since it uses as much as digits as its factorization.

421972987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 49.

The square root of 421972987 is about 20541.9810875193. The cubic root of 421972987 is about 750.0580618753.

The spelling of 421972987 in words is "four hundred twenty-one million, nine hundred seventy-two thousand, nine hundred eighty-seven".