157121640 has 384 divisors, whose sum is σ = 614476800. Its totient is φ = 35458560.

The previous prime is 157121639. The next prime is 157121663. The reversal of 157121640 is 46121751.

It is a happy number.

157121640 is a `hidden beast` number, since 1 + 5 + 7 + 12 + 1 + 640 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 5068425 + ... + 5068455.

It is an arithmetic number, because the mean of its divisors is an integer number (1600200).

Almost surely, 2^157121640 is an apocalyptic number.

157121640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 157121640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (307238400).

157121640 is an abundant number, since it is smaller than the sum of its proper divisors (457355160).

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

157121640 is a wasteful number, since it uses less digits than its factorization.

157121640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102 (or 73 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 157121640 is about 12534.8171107520. The cubic root of 157121640 is about 539.6083580005.

The spelling of 157121640 in words is "one hundred fifty-seven million, one hundred twenty-one thousand, six hundred forty".