145686421 has 2 divisors, whose sum is σ = 145686422. Its totient is φ = 145686420.

The previous prime is 145686403. The next prime is 145686449. The reversal of 145686421 is 124686541.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 145684900 + 1521 = 12070^2 + 39^2 .

It is a cyclic number.

It is not a de Polignac number, because 145686421 - 2⁷ = 145686293 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (145686491) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 72843210 + 72843211.

It is an arithmetic number, because the mean of its divisors is an integer number (72843211).

Almost surely, 2^145686421 is an apocalyptic number.

It is an amenable number.

145686421 is a deficient number, since it is larger than the sum of its proper divisors (1).

145686421 is an equidigital number, since it uses as much as digits as its factorization.

145686421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46080, while the sum is 37.

The square root of 145686421 is about 12070.0630072920. The cubic root of 145686421 is about 526.1864878224.

The spelling of 145686421 in words is "one hundred forty-five million, six hundred eighty-six thousand, four hundred twenty-one".