19657212401 has 2 divisors, whose sum is σ = 19657212402. Its totient is φ = 19657212400.

The previous prime is 19657212383. The next prime is 19657212403. The reversal of 19657212401 is 10421275691.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15844767376 + 3812445025 = 125876^2 + 61745^2 .

It is a cyclic number.

It is not a de Polignac number, because 19657212401 - 2³⁴ = 2477343217 is a prime.

Together with 19657212403, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19657212403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9828606200 + 9828606201.

It is an arithmetic number, because the mean of its divisors is an integer number (9828606201).

Almost surely, 2^19657212401 is an apocalyptic number.

It is an amenable number.

19657212401 is a deficient number, since it is larger than the sum of its proper divisors (1).

19657212401 is an equidigital number, since it uses as much as digits as its factorization.

19657212401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 30240, while the sum is 38.

The spelling of 19657212401 in words is "nineteen billion, six hundred fifty-seven million, two hundred twelve thousand, four hundred one".