151201821 has 4 divisors (see below), whose sum is σ = 201602432. Its totient is φ = 100801212.

The previous prime is 151201819. The next prime is 151201823. The reversal of 151201821 is 128102151.

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: 128102151 = 3 ⋅42700717.

It is an interprime number because it is at equal distance from previous prime (151201819) and next prime (151201823).

It is not a de Polignac number, because 151201821 - 2¹ = 151201819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (151201823) 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, 25200301 + ... + 25200306.

It is an arithmetic number, because the mean of its divisors is an integer number (50400608).

Almost surely, 2^151201821 is an apocalyptic number.

It is an amenable number.

151201821 is a deficient number, since it is larger than the sum of its proper divisors (50400611).

151201821 is an equidigital number, since it uses as much as digits as its factorization.

151201821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50400610.

The product of its (nonzero) digits is 160, while the sum is 21.

The square root of 151201821 is about 12296.4149653466. The cubic root of 151201821 is about 532.7445397581.

Adding to 151201821 its reverse (128102151), we get a palindrome (279303972).

The spelling of 151201821 in words is "one hundred fifty-one million, two hundred one thousand, eight hundred twenty-one".