157630402781 has 2 divisors, whose sum is σ = 157630402782. Its totient is φ = 157630402780.

The previous prime is 157630402777. The next prime is 157630402817. The reversal of 157630402781 is 187204036751.

Together with next prime (157630402817) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154724222500 + 2906180281 = 393350^2 + 53909^2 .

It is a cyclic number.

It is not a de Polignac number, because 157630402781 - 2² = 157630402777 is a prime.

It is a super-2 number, since 2×157630402781² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (157630402711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 78815201390 + 78815201391.

It is an arithmetic number, because the mean of its divisors is an integer number (78815201391).

Almost surely, 2^157630402781 is an apocalyptic number.

It is an amenable number.

157630402781 is a deficient number, since it is larger than the sum of its proper divisors (1).

157630402781 is an equidigital number, since it uses as much as digits as its factorization.

157630402781 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 282240, while the sum is 44.

The spelling of 157630402781 in words is "one hundred fifty-seven billion, six hundred thirty million, four hundred two thousand, seven hundred eighty-one".