157221012 has 24 divisors (see below), whose sum is σ = 395068576. Its totient is φ = 48375648.

The previous prime is 157221011. The next prime is 157221013. The reversal of 157221012 is 210122751.

It is an interprime number because it is at equal distance from previous prime (157221011) and next prime (157221013).

It is a super-2 number, since 2×157221012² = 49436893228608288, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 157221012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (157221011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 503758 + ... + 504069.

Almost surely, 2^157221012 is an apocalyptic number.

157221012 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

157221012 is an abundant number, since it is smaller than the sum of its proper divisors (237847564).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

157221012 is a wasteful number, since it uses less digits than its factorization.

157221012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1007847 (or 1007845 counting only the distinct ones).

The product of its (nonzero) digits is 280, while the sum is 21.

The square root of 157221012 is about 12538.7803234605. The cubic root of 157221012 is about 539.7220929413.

Adding to 157221012 its reverse (210122751), we get a palindrome (367343763).

The spelling of 157221012 in words is "one hundred fifty-seven million, two hundred twenty-one thousand, twelve".