151621997 has 8 divisors (see below), whose sum is σ = 161009856. Its totient is φ = 142286272.

The previous prime is 151621979. The next prime is 151622011. The reversal of 151621997 is 799126151.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 151621997 - 2¹⁸ = 151359853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (151621927) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6953 + ... + 18750.

It is an arithmetic number, because the mean of its divisors is an integer number (20126232).

Almost surely, 2^151621997 is an apocalyptic number.

151621997 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

151621997 is a deficient number, since it is larger than the sum of its proper divisors (9387859).

151621997 is a wasteful number, since it uses less digits than its factorization.

151621997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26067.

The product of its digits is 34020, while the sum is 41.

The square root of 151621997 is about 12313.4884171789. The cubic root of 151621997 is about 533.2375660947.

The spelling of 151621997 in words is "one hundred fifty-one million, six hundred twenty-one thousand, nine hundred ninety-seven".