21462747409 has 2 divisors, whose sum is σ = 21462747410. Its totient is φ = 21462747408.

The previous prime is 21462747403. The next prime is 21462747433. The reversal of 21462747409 is 90474726412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21275139600 + 187607809 = 145860^2 + 13697^2 .

It is a cyclic number.

It is not a de Polignac number, because 21462747409 - 2²¹ = 21460650257 is a prime.

It is not a weakly prime, because it can be changed into another prime (21462747403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10731373704 + 10731373705.

It is an arithmetic number, because the mean of its divisors is an integer number (10731373705).

Almost surely, 2^21462747409 is an apocalyptic number.

It is an amenable number.

21462747409 is a deficient number, since it is larger than the sum of its proper divisors (1).

21462747409 is an equidigital number, since it uses as much as digits as its factorization.

21462747409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 677376, while the sum is 46.

The spelling of 21462747409 in words is "twenty-one billion, four hundred sixty-two million, seven hundred forty-seven thousand, four hundred nine".