642206293 has 2 divisors, whose sum is σ = 642206294. Its totient is φ = 642206292.

The previous prime is 642206273. The next prime is 642206321. The reversal of 642206293 is 392602246.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 622652209 + 19554084 = 24953^2 + 4422^2 .

It is a cyclic number.

It is not a de Polignac number, because 642206293 - 2²⁹ = 105335381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (642206273) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 321103146 + 321103147.

It is an arithmetic number, because the mean of its divisors is an integer number (321103147).

Almost surely, 2^642206293 is an apocalyptic number.

It is an amenable number.

642206293 is a deficient number, since it is larger than the sum of its proper divisors (1).

642206293 is an equidigital number, since it uses as much as digits as its factorization.

642206293 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 34.

The square root of 642206293 is about 25341.7894593101. The cubic root of 642206293 is about 862.7630140393.

The spelling of 642206293 in words is "six hundred forty-two million, two hundred six thousand, two hundred ninety-three".