151630781 has 4 divisors (see below), whose sum is σ = 151853472. Its totient is φ = 151408092.

The previous prime is 151630753. The next prime is 151630793. The reversal of 151630781 is 187036151.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 187036151 = 1181 ⋅158371.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-151630781 is a prime.

It is a super-2 number, since 2×151630781² = 45983787493339922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (151630711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 110321 + ... + 111686.

It is an arithmetic number, because the mean of its divisors is an integer number (37963368).

Almost surely, 2^151630781 is an apocalyptic number.

It is an amenable number.

151630781 is a deficient number, since it is larger than the sum of its proper divisors (222691).

151630781 is an equidigital number, since it uses as much as digits as its factorization.

151630781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222690.

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 151630781 is about 12313.8450940395. The cubic root of 151630781 is about 533.2478633436.

The spelling of 151630781 in words is "one hundred fifty-one million, six hundred thirty thousand, seven hundred eighty-one".