42520210781 has 2 divisors, whose sum is σ = 42520210782. Its totient is φ = 42520210780.

The previous prime is 42520210723. The next prime is 42520210823. The reversal of 42520210781 is 18701202524.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35679432100 + 6840778681 = 188890^2 + 82709^2 .

It is a cyclic number.

It is not a de Polignac number, because 42520210781 - 2⁶ = 42520210717 is a prime.

It is a super-2 number, since 2×42520210781² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42520218781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21260105390 + 21260105391.

It is an arithmetic number, because the mean of its divisors is an integer number (21260105391).

Almost surely, 2^42520210781 is an apocalyptic number.

It is an amenable number.

42520210781 is a deficient number, since it is larger than the sum of its proper divisors (1).

42520210781 is an equidigital number, since it uses as much as digits as its factorization.

42520210781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8960, while the sum is 32.

The spelling of 42520210781 in words is "forty-two billion, five hundred twenty million, two hundred ten thousand, seven hundred eighty-one".