21214554397651 has 2 divisors, whose sum is σ = 21214554397652. Its totient is φ = 21214554397650.

The previous prime is 21214554397643. The next prime is 21214554397667. The reversal of 21214554397651 is 15679345541212.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21214554397651 - 2³ = 21214554397643 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21214554397592 and 21214554397601.

It is not a weakly prime, because it can be changed into another prime (21214554397601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10607277198825 + 10607277198826.

It is an arithmetic number, because the mean of its divisors is an integer number (10607277198826).

Almost surely, 2^{21214554397651} is an apocalyptic number.

21214554397651 is a deficient number, since it is larger than the sum of its proper divisors (1).

21214554397651 is an equidigital number, since it uses as much as digits as its factorization.

21214554397651 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072000, while the sum is 55.

The spelling of 21214554397651 in words is "twenty-one trillion, two hundred fourteen billion, five hundred fifty-four million, three hundred ninety-seven thousand, six hundred fifty-one".