157821970 has 16 divisors (see below), whose sum is σ = 284339160. Its totient is φ = 63071104.

The previous prime is 157821959. The next prime is 157822001. The reversal of 157821970 is 79128751.

It can be written as a sum of positive squares in 4 ways, for example, as 156775441 + 1046529 = 12521^2 + 1023^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5316 + ... + 18544.

Almost surely, 2^157821970 is an apocalyptic number.

157821970 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

157821970 is a deficient number, since it is larger than the sum of its proper divisors (126517190).

157821970 is a wasteful number, since it uses less digits than its factorization.

157821970 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14429.

The product of its (nonzero) digits is 35280, while the sum is 40.

The square root of 157821970 is about 12562.7214408344. The cubic root of 157821970 is about 540.4088924085.

The spelling of 157821970 in words is "one hundred fifty-seven million, eight hundred twenty-one thousand, nine hundred seventy".