151787021 has 2 divisors, whose sum is σ = 151787022. Its totient is φ = 151787020.

The previous prime is 151786993. The next prime is 151787023. The reversal of 151787021 is 120787151.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 119137225 + 32649796 = 10915^2 + 5714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-151787021 is a prime.

It is a Sophie Germain prime.

Together with 151787023, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (151787023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 75893510 + 75893511.

It is an arithmetic number, because the mean of its divisors is an integer number (75893511).

Almost surely, 2^151787021 is an apocalyptic number.

It is an amenable number.

151787021 is a deficient number, since it is larger than the sum of its proper divisors (1).

151787021 is an equidigital number, since it uses as much as digits as its factorization.

151787021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3920, while the sum is 32.

The square root of 151787021 is about 12320.1875391570. The cubic root of 151787021 is about 533.4309529209.

The spelling of 151787021 in words is "one hundred fifty-one million, seven hundred eighty-seven thousand, twenty-one".