280618421 has 2 divisors, whose sum is σ = 280618422. Its totient is φ = 280618420.

The previous prime is 280618367. The next prime is 280618427. The reversal of 280618421 is 124816082.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 143400625 + 137217796 = 11975^2 + 11714^2 .

It is a cyclic number.

It is not a de Polignac number, because 280618421 - 2⁶ = 280618357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (280618427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 140309210 + 140309211.

It is an arithmetic number, because the mean of its divisors is an integer number (140309211).

Almost surely, 2^280618421 is an apocalyptic number.

It is an amenable number.

280618421 is a deficient number, since it is larger than the sum of its proper divisors (1).

280618421 is an equidigital number, since it uses as much as digits as its factorization.

280618421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6144, while the sum is 32.

The square root of 280618421 is about 16751.6692004110. The cubic root of 280618421 is about 654.6945498082.

The spelling of 280618421 in words is "two hundred eighty million, six hundred eighteen thousand, four hundred twenty-one".