215138602457 has 2 divisors, whose sum is σ = 215138602458. Its totient is φ = 215138602456.

The previous prime is 215138602433. The next prime is 215138602493. The reversal of 215138602457 is 754206831512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 149632806976 + 65505795481 = 386824^2 + 255941^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-215138602457 is a prime.

It is not a weakly prime, because it can be changed into another prime (215138602157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107569301228 + 107569301229.

It is an arithmetic number, because the mean of its divisors is an integer number (107569301229).

Almost surely, 2^215138602457 is an apocalyptic number.

It is an amenable number.

215138602457 is a deficient number, since it is larger than the sum of its proper divisors (1).

215138602457 is an equidigital number, since it uses as much as digits as its factorization.

215138602457 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 403200, while the sum is 44.

The spelling of 215138602457 in words is "two hundred fifteen billion, one hundred thirty-eight million, six hundred two thousand, four hundred fifty-seven".