21437136157 has 2 divisors, whose sum is σ = 21437136158. Its totient is φ = 21437136156.

The previous prime is 21437136079. The next prime is 21437136179. The reversal of 21437136157 is 75163173412.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16254720036 + 5182416121 = 127494^2 + 71989^2 .

It is a cyclic number.

It is not a de Polignac number, because 21437136157 - 2⁷ = 21437136029 is a prime.

It is a super-2 number, since 2×21437136157² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21437136557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10718568078 + 10718568079.

It is an arithmetic number, because the mean of its divisors is an integer number (10718568079).

Almost surely, 2^21437136157 is an apocalyptic number.

It is an amenable number.

21437136157 is a deficient number, since it is larger than the sum of its proper divisors (1).

21437136157 is an equidigital number, since it uses as much as digits as its factorization.

21437136157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 40.

The spelling of 21437136157 in words is "twenty-one billion, four hundred thirty-seven million, one hundred thirty-six thousand, one hundred fifty-seven".